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+======
+Flake8
+======
+
+Flake8 is a wrapper around these tools:
+
+- PyFlakes
+- pep8
+- Ned Batchelder's McCabe script
+
+Flake8 runs all the tools by launching the single ``flake8`` script.
+It displays the warnings in a per-file, merged output.
+
+It also adds a few features:
+
+- files that contain this line are skipped::
+
+    # flake8: noqa
+
+- lines that contain a ``# noqa`` comment at the end will not issue warnings.
+- a Git and a Mercurial hook.
+- a McCabe complexity checker.
+- extendable through ``flake8.extension`` entry points.
+
+QuickStart
+==========
+
+::
+
+    pip install flake8
+
+To run flake8 just invoke it against any directory or Python module::
+
+    $ flake8 coolproject
+    coolproject/mod.py:97:1: F401 'shutil' imported but unused
+    coolproject/mod.py:625:17: E225 missing whitespace around operato
+    coolproject/mod.py:729:1: F811 redefinition of function 'readlines' from line 723
+    coolproject/mod.py:1028:1: F841 local variable 'errors' is assigned to but never used
+
+The outputs of PyFlakes *and* pep8 (and the optional plugins) are merged
+and returned.
+
+flake8 offers an extra option: --max-complexity, which will emit a warning if
+the McCabe complexity of a function is higher than the value.  By default it's
+deactivated::
+
+    $ flake8 --max-complexity 12 coolproject
+    coolproject/mod.py:97:1: F401 'shutil' imported but unused
+    coolproject/mod.py:625:17: E225 missing whitespace around operator
+    coolproject/mod.py:729:1: F811 redefinition of unused 'readlines' from line 723
+    coolproject/mod.py:939:1: C901 'Checker.check_all' is too complex (12)
+    coolproject/mod.py:1028:1: F841 local variable 'errors' is assigned to but never used
+    coolproject/mod.py:1204:1: C901 'selftest' is too complex (14)
+
+This feature is quite useful to detect over-complex code.  According to McCabe,
+anything that goes beyond 10 is too complex.
+See https://en.wikipedia.org/wiki/Cyclomatic_complexity.
+
+Documentation
+=============
+
+.. toctree::
+
+    api
+    config
+    vcs
+    buildout
+    setuptools
+    warnings
+
+Original Projects
+=================
+
+Flake8 is just a glue project, all the merits go to the creators of the original
+projects:
+
+- pep8: https://github.com/jcrocholl/pep8
+- PyFlakes: https://launchpad.net/pyflakes
+- McCabe: http://nedbatchelder.com/blog/200803/python_code_complexity_microtool.html