# Copyright (c) 2010-2020 Benjamin Peterson
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in all
# copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.
"""Utilities for writing code that runs on Python 2 and 3"""
from __future__ import annotations

import functools
import itertools
import operator
import sys
import types

__author__ = 'Benjamin Peterson <benjamin@python.org>'
__version__ = '1.16.0'


# Useful for very coarse version differentiation.
PY2 = sys.version_info[0] == 2
PY3 = sys.version_info[0] == 3
PY34 = sys.version_info[0:2] >= (3, 4)

if PY3:
    string_types = str,
    integer_types = int,
    class_types = type,
    text_type = str
    binary_type = bytes

    MAXSIZE = sys.maxsize
else:
    string_types = basestring,
    integer_types = (int, long)
    class_types = (type, types.ClassType)
    text_type = unicode
    binary_type = str

    if sys.platform.startswith('java'):
        # Jython always uses 32 bits.
        MAXSIZE = int((1 << 31) - 1)
    else:
        # It's possible to have sizeof(long) != sizeof(Py_ssize_t).
        class X:

            def __len__(self):
                return 1 << 31
        try:
            len(X())
        except OverflowError:
            # 32-bit
            MAXSIZE = int((1 << 31) - 1)
        else:
            # 64-bit
            MAXSIZE = int((1 << 63) - 1)
        del X

if PY34:
    from importlib.util import spec_from_loader
else:
    spec_from_loader = None


def _add_doc(func, doc):
    """Add documentation to a function."""
    func.__doc__ = doc


def _import_module(name):
    """Import module, returning the module after the last dot."""
    __import__(name)
    return sys.modules[name]


class _LazyDescr:

    def __init__(self, name):
        self.name = name

    def __get__(self, obj, tp):
        result = self._resolve()
        setattr(obj, self.name, result)  # Invokes __set__.
        try:
            # This is a bit ugly, but it avoids running this again by
            # removing this descriptor.
            delattr(obj.__class__, self.name)
        except AttributeError:
            pass
        return result


class MovedModule(_LazyDescr):

    def __init__(self, name, old, new=None):
        super().__init__(name)
        if PY3:
            if new is None:
                new = name
            self.mod = new
        else:
            self.mod = old

    def _resolve(self):
        return _import_module(self.mod)

    def __getattr__(self, attr):
        _module = self._resolve()
        value = getattr(_module, attr)
        setattr(self, attr, value)
        return value


class _LazyModule(types.ModuleType):

    def __init__(self, name):
        super().__init__(name)
        self.__doc__ = self.__class__.__doc__

    def __dir__(self):
        attrs = ['__doc__', '__name__']
        attrs += [attr.name for attr in self._moved_attributes]
        return attrs

    # Subclasses should override this
    _moved_attributes = []


class MovedAttribute(_LazyDescr):

    def __init__(self, name, old_mod, new_mod, old_attr=None, new_attr=None):
        super().__init__(name)
        if PY3:
            if new_mod is None:
                new_mod = name
            self.mod = new_mod
            if new_attr is None:
                if old_attr is None:
                    new_attr = name
                else:
                    new_attr = old_attr
            self.attr = new_attr
        else:
            self.mod = old_mod
            if old_attr is None:
                old_attr = name
            self.attr = old_attr

    def _resolve(self):
        module = _import_module(self.mod)
        return getattr(module, self.attr)


class _SixMetaPathImporter:

    """
    A meta path importer to import six.moves and its submodules.

    This class implements a PEP302 finder and loader. It should be compatible
    with Python 2.5 and all existing versions of Python3
    """

    def __init__(self, six_module_name):
        self.name = six_module_name
        self.known_modules = {}

    def _add_module(self, mod, *fullnames):
        for fullname in fullnames:
            self.known_modules[self.name + '.' + fullname] = mod

    def _get_module(self, fullname):
        return self.known_modules[self.name + '.' + fullname]

    def find_module(self, fullname, path=None):
        if fullname in self.known_modules:
            return self
        return None

    def find_spec(self, fullname, path, target=None):
        if fullname in self.known_modules:
            return spec_from_loader(fullname, self)
        return None

    def __get_module(self, fullname):
        try:
            return self.known_modules[fullname]
        except KeyError:
            raise ImportError('This loader does not know module ' + fullname)

    def load_module(self, fullname):
        try:
            # in case of a reload
            return sys.modules[fullname]
        except KeyError:
            pass
        mod = self.__get_module(fullname)
        if isinstance(mod, MovedModule):
            mod = mod._resolve()
        else:
            mod.__loader__ = self
        sys.modules[fullname] = mod
        return mod

    def is_package(self, fullname):
        """
        Return true, if the named module is a package.

        We need this method to get correct spec objects with
        Python 3.4 (see PEP451)
        """
        return hasattr(self.__get_module(fullname), '__path__')

    def get_code(self, fullname):
        """Return None

        Required, if is_package is implemented"""
        self.__get_module(fullname)  # eventually raises ImportError
        return None
    get_source = get_code  # same as get_code

    def create_module(self, spec):
        return self.load_module(spec.name)

    def exec_module(self, module):
        pass


_importer = _SixMetaPathImporter(__name__)


class _MovedItems(_LazyModule):

    """Lazy loading of moved objects"""
    __path__ = []  # mark as package


_moved_attributes = [
    MovedAttribute('cStringIO', 'cStringIO', 'io', 'StringIO'),
    MovedAttribute('filter', 'itertools', 'builtins', 'ifilter', 'filter'),
    MovedAttribute('filterfalse', 'itertools', 'itertools', 'ifilterfalse', 'filterfalse'),
    MovedAttribute('input', '__builtin__', 'builtins', 'raw_input', 'input'),
    MovedAttribute('intern', '__builtin__', 'sys'),
    MovedAttribute('map', 'itertools', 'builtins', 'imap', 'map'),
    MovedAttribute('getcwd', 'os', 'os', 'getcwdu', 'getcwd'),
    MovedAttribute('getcwdb', 'os', 'os', 'getcwd', 'getcwdb'),
    MovedAttribute('getoutput', 'commands', 'subprocess'),
    MovedAttribute('range', '__builtin__', 'builtins', 'xrange', 'range'),
    MovedAttribute('reload_module', '__builtin__', 'importlib' if PY34 else 'imp', 'reload'),
    MovedAttribute('reduce', '__builtin__', 'functools'),
    MovedAttribute('shlex_quote', 'pipes', 'shlex', 'quote'),
    MovedAttribute('StringIO', 'StringIO', 'io'),
    MovedAttribute('UserDict', 'UserDict', 'collections'),
    MovedAttribute('UserList', 'UserList', 'collections'),
    MovedAttribute('UserString', 'UserString', 'collections'),
    MovedAttribute('xrange', '__builtin__', 'builtins', 'xrange', 'range'),
    MovedAttribute('zip', 'itertools', 'builtins', 'izip', 'zip'),
    MovedAttribute('zip_longest', 'itertools', 'itertools', 'izip_longest', 'zip_longest'),
    MovedModule('builtins', '__builtin__'),
    MovedModule('configparser', 'ConfigParser'),
    MovedModule('collections_abc', 'collections', 'collections.abc' if sys.version_info >= (3, 3) else 'collections'),
    MovedModule('copyreg', 'copy_reg'),
    MovedModule('dbm_gnu', 'gdbm', 'dbm.gnu'),
    MovedModule('dbm_ndbm', 'dbm', 'dbm.ndbm'),
    MovedModule('_dummy_thread', 'dummy_thread', '_dummy_thread' if sys.version_info < (3, 9) else '_thread'),
    MovedModule('http_cookiejar', 'cookielib', 'http.cookiejar'),
    MovedModule('http_cookies', 'Cookie', 'http.cookies'),
    MovedModule('html_entities', 'htmlentitydefs', 'html.entities'),
    MovedModule('html_parser', 'HTMLParser', 'html.parser'),
    MovedModule('http_client', 'httplib', 'http.client'),
    MovedModule('email_mime_base', 'email.MIMEBase', 'email.mime.base'),
    MovedModule('email_mime_image', 'email.MIMEImage', 'email.mime.image'),
    MovedModule('email_mime_multipart', 'email.MIMEMultipart', 'email.mime.multipart'),
    MovedModule('email_mime_nonmultipart', 'email.MIMENonMultipart', 'email.mime.nonmultipart'),
    MovedModule('email_mime_text', 'email.MIMEText', 'email.mime.text'),
    MovedModule('BaseHTTPServer', 'BaseHTTPServer', 'http.server'),
    MovedModule('CGIHTTPServer', 'CGIHTTPServer', 'http.server'),
    MovedModule('SimpleHTTPServer', 'SimpleHTTPServer', 'http.server'),
    MovedModule('cPickle', 'cPickle', 'pickle'),
    MovedModule('queue', 'Queue'),
    MovedModule('reprlib', 'repr'),
    MovedModule('socketserver', 'SocketServer'),
    MovedModule('_thread', 'thread', '_thread'),
    MovedModule('tkinter', 'Tkinter'),
    MovedModule('tkinter_dialog', 'Dialog', 'tkinter.dialog'),
    MovedModule('tkinter_filedialog', 'FileDialog', 'tkinter.filedialog'),
    MovedModule('tkinter_scrolledtext', 'ScrolledText', 'tkinter.scrolledtext'),
    MovedModule('tkinter_simpledialog', 'SimpleDialog', 'tkinter.simpledialog'),
    MovedModule('tkinter_tix', 'Tix', 'tkinter.tix'),
    MovedModule('tkinter_ttk', 'ttk', 'tkinter.ttk'),
    MovedModule('tkinter_constants', 'Tkconstants', 'tkinter.constants'),
    MovedModule('tkinter_dnd', 'Tkdnd', 'tkinter.dnd'),
    MovedModule(
        'tkinter_colorchooser', 'tkColorChooser',
        'tkinter.colorchooser',
    ),
    MovedModule(
        'tkinter_commondialog', 'tkCommonDialog',
        'tkinter.commondialog',
    ),
    MovedModule('tkinter_tkfiledialog', 'tkFileDialog', 'tkinter.filedialog'),
    MovedModule('tkinter_font', 'tkFont', 'tkinter.font'),
    MovedModule('tkinter_messagebox', 'tkMessageBox', 'tkinter.messagebox'),
    MovedModule(
        'tkinter_tksimpledialog', 'tkSimpleDialog',
        'tkinter.simpledialog',
    ),
    MovedModule('urllib_parse', __name__ + '.moves.urllib_parse', 'urllib.parse'),
    MovedModule('urllib_error', __name__ + '.moves.urllib_error', 'urllib.error'),
    MovedModule('urllib', __name__ + '.moves.urllib', __name__ + '.moves.urllib'),
    MovedModule('urllib_robotparser', 'robotparser', 'urllib.robotparser'),
    MovedModule('xmlrpc_client', 'xmlrpclib', 'xmlrpc.client'),
    MovedModule('xmlrpc_server', 'SimpleXMLRPCServer', 'xmlrpc.server'),
]
# Add windows specific modules.
if sys.platform == 'win32':
    _moved_attributes += [
        MovedModule('winreg', '_winreg'),
    ]

for attr in _moved_attributes:
    setattr(_MovedItems, attr.name, attr)
    if isinstance(attr, MovedModule):
        _importer._add_module(attr, 'moves.' + attr.name)
del attr

_MovedItems._moved_attributes = _moved_attributes

moves = _MovedItems(__name__ + '.moves')
_importer._add_module(moves, 'moves')


class Module_six_moves_urllib_parse(_LazyModule):

    """Lazy loading of moved objects in six.moves.urllib_parse"""


_urllib_parse_moved_attributes = [
    MovedAttribute('ParseResult', 'urlparse', 'urllib.parse'),
    MovedAttribute('SplitResult', 'urlparse', 'urllib.parse'),
    MovedAttribute('parse_qs', 'urlparse', 'urllib.parse'),
    MovedAttribute('parse_qsl', 'urlparse', 'urllib.parse'),
    MovedAttribute('urldefrag', 'urlparse', 'urllib.parse'),
    MovedAttribute('urljoin', 'urlparse', 'urllib.parse'),
    MovedAttribute('urlparse', 'urlparse', 'urllib.parse'),
    MovedAttribute('urlsplit', 'urlparse', 'urllib.parse'),
    MovedAttribute('urlunparse', 'urlparse', 'urllib.parse'),
    MovedAttribute('urlunsplit', 'urlparse', 'urllib.parse'),
    MovedAttribute('quote', 'urllib', 'urllib.parse'),
    MovedAttribute('quote_plus', 'urllib', 'urllib.parse'),
    MovedAttribute('unquote', 'urllib', 'urllib.parse'),
    MovedAttribute('unquote_plus', 'urllib', 'urllib.parse'),
    MovedAttribute('unquote_to_bytes', 'urllib', 'urllib.parse', 'unquote', 'unquote_to_bytes'),
    MovedAttribute('urlencode', 'urllib', 'urllib.parse'),
    MovedAttribute('splitquery', 'urllib', 'urllib.parse'),
    MovedAttribute('splittag', 'urllib', 'urllib.parse'),
    MovedAttribute('splituser', 'urllib', 'urllib.parse'),
    MovedAttribute('splitvalue', 'urllib', 'urllib.parse'),
    MovedAttribute('uses_fragment', 'urlparse', 'urllib.parse'),
    MovedAttribute('uses_netloc', 'urlparse', 'urllib.parse'),
    MovedAttribute('uses_params', 'urlparse', 'urllib.parse'),
    MovedAttribute('uses_query', 'urlparse', 'urllib.parse'),
    MovedAttribute('uses_relative', 'urlparse', 'urllib.parse'),
]
for attr in _urllib_parse_moved_attributes:
    setattr(Module_six_moves_urllib_parse, attr.name, attr)
del attr

Module_six_moves_urllib_parse._moved_attributes = _urllib_parse_moved_attributes

_importer._add_module(
    Module_six_moves_urllib_parse(__name__ + '.moves.urllib_parse'),
    'moves.urllib_parse', 'moves.urllib.parse',
)


class Module_six_moves_urllib_error(_LazyModule):

    """Lazy loading of moved objects in six.moves.urllib_error"""


_urllib_error_moved_attributes = [
    MovedAttribute('URLError', 'urllib2', 'urllib.error'),
    MovedAttribute('HTTPError', 'urllib2', 'urllib.error'),
    MovedAttribute('ContentTooShortError', 'urllib', 'urllib.error'),
]
for attr in _urllib_error_moved_attributes:
    setattr(Module_six_moves_urllib_error, attr.name, attr)
del attr

Module_six_moves_urllib_error._moved_attributes = _urllib_error_moved_attributes

_importer._add_module(
    Module_six_moves_urllib_error(__name__ + '.moves.urllib.error'),
    'moves.urllib_error', 'moves.urllib.error',
)


class Module_six_moves_urllib_request(_LazyModule):

    """Lazy loading of moved objects in six.moves.urllib_request"""


_urllib_request_moved_attributes = [
    MovedAttribute('urlopen', 'urllib2', 'urllib.request'),
    MovedAttribute('install_opener', 'urllib2', 'urllib.request'),
    MovedAttribute('build_opener', 'urllib2', 'urllib.request'),
    MovedAttribute('pathname2url', 'urllib', 'urllib.request'),
    MovedAttribute('url2pathname', 'urllib', 'urllib.request'),
    MovedAttribute('getproxies', 'urllib', 'urllib.request'),
    MovedAttribute('Request', 'urllib2', 'urllib.request'),
    MovedAttribute('OpenerDirector', 'urllib2', 'urllib.request'),
    MovedAttribute('HTTPDefaultErrorHandler', 'urllib2', 'urllib.request'),
    MovedAttribute('HTTPRedirectHandler', 'urllib2', 'urllib.request'),
    MovedAttribute('HTTPCookieProcessor', 'urllib2', 'urllib.request'),
    MovedAttribute('ProxyHandler', 'urllib2', 'urllib.request'),
    MovedAttribute('BaseHandler', 'urllib2', 'urllib.request'),
    MovedAttribute('HTTPPasswordMgr', 'urllib2', 'urllib.request'),
    MovedAttribute('HTTPPasswordMgrWithDefaultRealm', 'urllib2', 'urllib.request'),
    MovedAttribute('AbstractBasicAuthHandler', 'urllib2', 'urllib.request'),
    MovedAttribute('HTTPBasicAuthHandler', 'urllib2', 'urllib.request'),
    MovedAttribute('ProxyBasicAuthHandler', 'urllib2', 'urllib.request'),
    MovedAttribute('AbstractDigestAuthHandler', 'urllib2', 'urllib.request'),
    MovedAttribute('HTTPDigestAuthHandler', 'urllib2', 'urllib.request'),
    MovedAttribute('ProxyDigestAuthHandler', 'urllib2', 'urllib.request'),
    MovedAttribute('HTTPHandler', 'urllib2', 'urllib.request'),
    MovedAttribute('HTTPSHandler', 'urllib2', 'urllib.request'),
    MovedAttribute('FileHandler', 'urllib2', 'urllib.request'),
    MovedAttribute('FTPHandler', 'urllib2', 'urllib.request'),
    MovedAttribute('CacheFTPHandler', 'urllib2', 'urllib.request'),
    MovedAttribute('UnknownHandler', 'urllib2', 'urllib.request'),
    MovedAttribute('HTTPErrorProcessor', 'urllib2', 'urllib.request'),
    MovedAttribute('urlretrieve', 'urllib', 'urllib.request'),
    MovedAttribute('urlcleanup', 'urllib', 'urllib.request'),
    MovedAttribute('URLopener', 'urllib', 'urllib.request'),
    MovedAttribute('FancyURLopener', 'urllib', 'urllib.request'),
    MovedAttribute('proxy_bypass', 'urllib', 'urllib.request'),
    MovedAttribute('parse_http_list', 'urllib2', 'urllib.request'),
    MovedAttribute('parse_keqv_list', 'urllib2', 'urllib.request'),
]
for attr in _urllib_request_moved_attributes:
    setattr(Module_six_moves_urllib_request, attr.name, attr)
del attr

Module_six_moves_urllib_request._moved_attributes = _urllib_request_moved_attributes

_importer._add_module(
    Module_six_moves_urllib_request(__name__ + '.moves.urllib.request'),
    'moves.urllib_request', 'moves.urllib.request',
)


class Module_six_moves_urllib_response(_LazyModule):

    """Lazy loading of moved objects in six.moves.urllib_response"""


_urllib_response_moved_attributes = [
    MovedAttribute('addbase', 'urllib', 'urllib.response'),
    MovedAttribute('addclosehook', 'urllib', 'urllib.response'),
    MovedAttribute('addinfo', 'urllib', 'urllib.response'),
    MovedAttribute('addinfourl', 'urllib', 'urllib.response'),
]
for attr in _urllib_response_moved_attributes:
    setattr(Module_six_moves_urllib_response, attr.name, attr)
del attr

Module_six_moves_urllib_response._moved_attributes = _urllib_response_moved_attributes

_importer._add_module(
    Module_six_moves_urllib_response(__name__ + '.moves.urllib.response'),
    'moves.urllib_response', 'moves.urllib.response',
)


class Module_six_moves_urllib_robotparser(_LazyModule):

    """Lazy loading of moved objects in six.moves.urllib_robotparser"""


_urllib_robotparser_moved_attributes = [
    MovedAttribute('RobotFileParser', 'robotparser', 'urllib.robotparser'),
]
for attr in _urllib_robotparser_moved_attributes:
    setattr(Module_six_moves_urllib_robotparser, attr.name, attr)
del attr

Module_six_moves_urllib_robotparser._moved_attributes = _urllib_robotparser_moved_attributes

_importer._add_module(
    Module_six_moves_urllib_robotparser(__name__ + '.moves.urllib.robotparser'),
    'moves.urllib_robotparser', 'moves.urllib.robotparser',
)


class Module_six_moves_urllib(types.ModuleType):

    """Create a six.moves.urllib namespace that resembles the Python 3 namespace"""
    __path__ = []  # mark as package
    parse = _importer._get_module('moves.urllib_parse')
    error = _importer._get_module('moves.urllib_error')
    request = _importer._get_module('moves.urllib_request')
    response = _importer._get_module('moves.urllib_response')
    robotparser = _importer._get_module('moves.urllib_robotparser')

    def __dir__(self):
        return ['parse', 'error', 'request', 'response', 'robotparser']


_importer._add_module(
    Module_six_moves_urllib(__name__ + '.moves.urllib'),
    'moves.urllib',
)


def add_move(move):
    """Add an item to six.moves."""
    setattr(_MovedItems, move.name, move)


def remove_move(name):
    """Remove item from six.moves."""
    try:
        delattr(_MovedItems, name)
    except AttributeError:
        try:
            del moves.__dict__[name]
        except KeyError:
            raise AttributeError('no such move, {!r}'.format(name))


if PY3:
    _meth_func = '__func__'
    _meth_self = '__self__'

    _func_closure = '__closure__'
    _func_code = '__code__'
    _func_defaults = '__defaults__'
    _func_globals = '__globals__'
else:
    _meth_func = 'im_func'
    _meth_self = 'im_self'

    _func_closure = 'func_closure'
    _func_code = 'func_code'
    _func_defaults = 'func_defaults'
    _func_globals = 'func_globals'


try:
    advance_iterator = next
except NameError:
    def advance_iterator(it):
        return it.next()
next = advance_iterator


try:
    callable = callable
except NameError:
    def callable(obj):
        return any('__call__' in klass.__dict__ for klass in type(obj).__mro__)


if PY3:
    def get_unbound_function(unbound):
        return unbound

    create_bound_method = types.MethodType

    def create_unbound_method(func, cls):
        return func

    Iterator = object
else:
    def get_unbound_function(unbound):
        return unbound.im_func

    def create_bound_method(func, obj):
        return types.MethodType(func, obj, obj.__class__)

    def create_unbound_method(func, cls):
        return types.MethodType(func, None, cls)

    class Iterator:

        def next(self):
            return type(self).__next__(self)

    callable = callable
_add_doc(
    get_unbound_function,
    """Get the function out of a possibly unbound function""",
)


get_method_function = operator.attrgetter(_meth_func)
get_method_self = operator.attrgetter(_meth_self)
get_function_closure = operator.attrgetter(_func_closure)
get_function_code = operator.attrgetter(_func_code)
get_function_defaults = operator.attrgetter(_func_defaults)
get_function_globals = operator.attrgetter(_func_globals)


if PY3:
    def iterkeys(d, **kw):
        return iter(d.keys(**kw))

    def itervalues(d, **kw):
        return iter(d.values(**kw))

    def iteritems(d, **kw):
        return iter(d.items(**kw))

    def iterlists(d, **kw):
        return iter(d.lists(**kw))

    viewkeys = operator.methodcaller('keys')

    viewvalues = operator.methodcaller('values')

    viewitems = operator.methodcaller('items')
else:
    def iterkeys(d, **kw):
        return d.iterkeys(**kw)

    def itervalues(d, **kw):
        return d.itervalues(**kw)

    def iteritems(d, **kw):
        return d.iteritems(**kw)

    def iterlists(d, **kw):
        return d.iterlists(**kw)

    viewkeys = operator.methodcaller('viewkeys')

    viewvalues = operator.methodcaller('viewvalues')

    viewitems = operator.methodcaller('viewitems')

_add_doc(iterkeys, 'Return an iterator over the keys of a dictionary.')
_add_doc(itervalues, 'Return an iterator over the values of a dictionary.')
_add_doc(
    iteritems,
    'Return an iterator over the (key, value) pairs of a dictionary.',
)
_add_doc(
    iterlists,
    'Return an iterator over the (key, [values]) pairs of a dictionary.',
)


if PY3:
    def b(s):
        return s.encode('latin-1')

    def u(s):
        return s
    unichr = chr
    import struct
    int2byte = struct.Struct('>B').pack
    del struct
    byte2int = operator.itemgetter(0)
    indexbytes = operator.getitem
    iterbytes = iter
    import io
    StringIO = io.StringIO
    BytesIO = io.BytesIO
    del io
    _assertCountEqual = 'assertCountEqual'
    if sys.version_info[1] <= 1:
        _assertRaisesRegex = 'assertRaisesRegexp'
        _assertRegex = 'assertRegexpMatches'
        _assertNotRegex = 'assertNotRegexpMatches'
    else:
        _assertRaisesRegex = 'assertRaisesRegex'
        _assertRegex = 'assertRegex'
        _assertNotRegex = 'assertNotRegex'
else:
    def b(s):
        return s
    # Workaround for standalone backslash

    def u(s):
        return unicode(s.replace(r'\\', r'\\\\'), 'unicode_escape')
    unichr = unichr
    int2byte = chr

    def byte2int(bs):
        return ord(bs[0])

    def indexbytes(buf, i):
        return ord(buf[i])
    iterbytes = functools.partial(itertools.imap, ord)
    import StringIO
    StringIO = BytesIO = StringIO.StringIO
    _assertCountEqual = 'assertItemsEqual'
    _assertRaisesRegex = 'assertRaisesRegexp'
    _assertRegex = 'assertRegexpMatches'
    _assertNotRegex = 'assertNotRegexpMatches'
_add_doc(b, """Byte literal""")
_add_doc(u, """Text literal""")


def assertCountEqual(self, *args, **kwargs):
    return getattr(self, _assertCountEqual)(*args, **kwargs)


def assertRaisesRegex(self, *args, **kwargs):
    return getattr(self, _assertRaisesRegex)(*args, **kwargs)


def assertRegex(self, *args, **kwargs):
    return getattr(self, _assertRegex)(*args, **kwargs)


def assertNotRegex(self, *args, **kwargs):
    return getattr(self, _assertNotRegex)(*args, **kwargs)


if PY3:
    exec_ = getattr(moves.builtins, 'exec')

    def reraise(tp, value, tb=None):
        try:
            if value is None:
                value = tp()
            if value.__traceback__ is not tb:
                raise value.with_traceback(tb)
            raise value
        finally:
            value = None
            tb = None

else:
    def exec_(_code_, _globs_=None, _locs_=None):
        """Execute code in a namespace."""
        if _globs_ is None:
            frame = sys._getframe(1)
            _globs_ = frame.f_globals
            if _locs_ is None:
                _locs_ = frame.f_locals
            del frame
        elif _locs_ is None:
            _locs_ = _globs_
        exec("""exec _code_ in _globs_, _locs_""")

    exec_("""def reraise(tp, value, tb=None):
    try:
        raise tp, value, tb
    finally:
        tb = None
""")


if sys.version_info[:2] > (3,):
    exec_("""def raise_from(value, from_value):
    try:
        raise value from from_value
    finally:
        value = None
""")
else:
    def raise_from(value, from_value):
        raise value


print_ = getattr(moves.builtins, 'print', None)
if print_ is None:
    def print_(*args, **kwargs):
        """The new-style print function for Python 2.4 and 2.5."""
        fp = kwargs.pop('file', sys.stdout)
        if fp is None:
            return

        def write(data):
            if not isinstance(data, basestring):
                data = str(data)
            # If the file has an encoding, encode unicode with it.
            if (
                isinstance(fp, file) and
                isinstance(data, unicode) and
                fp.encoding is not None
            ):
                errors = getattr(fp, 'errors', None)
                if errors is None:
                    errors = 'strict'
                data = data.encode(fp.encoding, errors)
            fp.write(data)
        want_unicode = False
        sep = kwargs.pop('sep', None)
        if sep is not None:
            if isinstance(sep, unicode):
                want_unicode = True
            elif not isinstance(sep, str):
                raise TypeError('sep must be None or a string')
        end = kwargs.pop('end', None)
        if end is not None:
            if isinstance(end, unicode):
                want_unicode = True
            elif not isinstance(end, str):
                raise TypeError('end must be None or a string')
        if kwargs:
            raise TypeError('invalid keyword arguments to print()')
        if not want_unicode:
            for arg in args:
                if isinstance(arg, unicode):
                    want_unicode = True
                    break
        if want_unicode:
            newline = unicode('\n')
            space = unicode(' ')
        else:
            newline = '\n'
            space = ' '
        if sep is None:
            sep = space
        if end is None:
            end = newline
        for i, arg in enumerate(args):
            if i:
                write(sep)
            write(arg)
        write(end)
if sys.version_info[:2] < (3, 3):
    _print = print_

    def print_(*args, **kwargs):
        fp = kwargs.get('file', sys.stdout)
        flush = kwargs.pop('flush', False)
        _print(*args, **kwargs)
        if flush and fp is not None:
            fp.flush()

_add_doc(reraise, """Reraise an exception.""")

if sys.version_info[0:2] < (3, 4):
    # This does exactly the same what the :func:`py3:functools.update_wrapper`
    # function does on Python versions after 3.2. It sets the ``__wrapped__``
    # attribute on ``wrapper`` object and it doesn't raise an error if any of
    # the attributes mentioned in ``assigned`` and ``updated`` are missing on
    # ``wrapped`` object.
    def _update_wrapper(
        wrapper, wrapped,
        assigned=functools.WRAPPER_ASSIGNMENTS,
        updated=functools.WRAPPER_UPDATES,
    ):
        for attr in assigned:
            try:
                value = getattr(wrapped, attr)
            except AttributeError:
                continue
            else:
                setattr(wrapper, attr, value)
        for attr in updated:
            getattr(wrapper, attr).update(getattr(wrapped, attr, {}))
        wrapper.__wrapped__ = wrapped
        return wrapper
    _update_wrapper.__doc__ = functools.update_wrapper.__doc__

    def wraps(
        wrapped, assigned=functools.WRAPPER_ASSIGNMENTS,
        updated=functools.WRAPPER_UPDATES,
    ):
        return functools.partial(
            _update_wrapper, wrapped=wrapped,
            assigned=assigned, updated=updated,
        )
    wraps.__doc__ = functools.wraps.__doc__

else:
    wraps = functools.wraps


def with_metaclass(meta, *bases):
    """Create a base class with a metaclass."""
    # This requires a bit of explanation: the basic idea is to make a dummy
    # metaclass for one level of class instantiation that replaces itself with
    # the actual metaclass.
    class metaclass(type):

        def __new__(cls, name, this_bases, d):
            if sys.version_info[:2] >= (3, 7):
                # This version introduced PEP 560 that requires a bit
                # of extra care (we mimic what is done by __build_class__).
                resolved_bases = types.resolve_bases(bases)
                if resolved_bases is not bases:
                    d['__orig_bases__'] = bases
            else:
                resolved_bases = bases
            return meta(name, resolved_bases, d)

        @classmethod
        def __prepare__(cls, name, this_bases):
            return meta.__prepare__(name, bases)
    return type.__new__(metaclass, 'temporary_class', (), {})


def add_metaclass(metaclass):
    """Class decorator for creating a class with a metaclass."""
    def wrapper(cls):
        orig_vars = cls.__dict__.copy()
        slots = orig_vars.get('__slots__')
        if slots is not None:
            if isinstance(slots, str):
                slots = [slots]
            for slots_var in slots:
                orig_vars.pop(slots_var)
        orig_vars.pop('__dict__', None)
        orig_vars.pop('__weakref__', None)
        if hasattr(cls, '__qualname__'):
            orig_vars['__qualname__'] = cls.__qualname__
        return metaclass(cls.__name__, cls.__bases__, orig_vars)
    return wrapper


def ensure_binary(s, encoding='utf-8', errors='strict'):
    """Coerce **s** to six.binary_type.

    For Python 2:
      - `unicode` -> encoded to `str`
      - `str` -> `str`

    For Python 3:
      - `str` -> encoded to `bytes`
      - `bytes` -> `bytes`
    """
    if isinstance(s, binary_type):
        return s
    if isinstance(s, text_type):
        return s.encode(encoding, errors)
    raise TypeError("not expecting type '%s'" % type(s))


def ensure_str(s, encoding='utf-8', errors='strict'):
    """Coerce *s* to `str`.

    For Python 2:
      - `unicode` -> encoded to `str`
      - `str` -> `str`

    For Python 3:
      - `str` -> `str`
      - `bytes` -> decoded to `str`
    """
    # Optimization: Fast return for the common case.
    if type(s) is str:
        return s
    if PY2 and isinstance(s, text_type):
        return s.encode(encoding, errors)
    elif PY3 and isinstance(s, binary_type):
        return s.decode(encoding, errors)
    elif not isinstance(s, (text_type, binary_type)):
        raise TypeError("not expecting type '%s'" % type(s))
    return s


def ensure_text(s, encoding='utf-8', errors='strict'):
    """Coerce *s* to six.text_type.

    For Python 2:
      - `unicode` -> `unicode`
      - `str` -> `unicode`

    For Python 3:
      - `str` -> `str`
      - `bytes` -> decoded to `str`
    """
    if isinstance(s, binary_type):
        return s.decode(encoding, errors)
    elif isinstance(s, text_type):
        return s
    else:
        raise TypeError("not expecting type '%s'" % type(s))


def python_2_unicode_compatible(klass):
    """
    A class decorator that defines __unicode__ and __str__ methods under Python 2.
    Under Python 3 it does nothing.

    To support Python 2 and 3 with a single code base, define a __str__ method
    returning text and apply this decorator to the class.
    """
    if PY2:
        if '__str__' not in klass.__dict__:
            raise ValueError(
                '@python_2_unicode_compatible cannot be applied '
                "to %s because it doesn't define __str__()." %
                klass.__name__,
            )
        klass.__unicode__ = klass.__str__
        klass.__str__ = lambda self: self.__unicode__().encode('utf-8')
    return klass


# Complete the moves implementation.
# This code is at the end of this module to speed up module loading.
# Turn this module into a package.
__path__ = []  # required for PEP 302 and PEP 451
__package__ = __name__  # see PEP 366 @ReservedAssignment
if globals().get('__spec__') is not None:
    __spec__.submodule_search_locations = []  # PEP 451 @UndefinedVariable
# Remove other six meta path importers, since they cause problems. This can
# happen if six is removed from sys.modules and then reloaded. (Setuptools does
# this for some reason.)
if sys.meta_path:
    for i, importer in enumerate(sys.meta_path):
        # Here's some real nastiness: Another "instance" of the six module might
        # be floating around. Therefore, we can't use isinstance() to check for
        # the six meta path importer, since the other six instance will have
        # inserted an importer with different class.
        if (
            type(importer).__name__ == '_SixMetaPathImporter' and
            importer.name == __name__
        ):
            del sys.meta_path[i]
            break
    del i, importer
# Finally, add the importer to the meta path import hook.
sys.meta_path.append(_importer)