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+===================
+ Utility Functions
+===================
+
+Flake8 has a few utility functions that it uses and provides to plugins.
+
+.. autofunction:: flake8.utils.parse_comma_separated_list
+
+:func:`~flake8.utils.parse_comma_separated_list` takes either a string like
+
+.. code-block:: python
+
+    "E121,W123,F904"
+    "E121,\nW123,\nF804"
+    "E121,\n\tW123,\n\tF804"
+
+Or it will take a list of strings (potentially with whitespace) such as
+
+.. code-block:: python
+
+    ["   E121\n", "\t\nW123   ", "\n\tF904\n    "]
+
+And converts it to a list that looks as follows
+
+.. code-block:: python
+
+    ["E121", "W123", "F904"]
+
+This function helps normalize any kind of comma-separated input you or Flake8
+might receive. This is most helpful when taking advantage of Flake8's
+additional parameters to :class:`~flake8.options.manager.Option`.
+
+.. autofunction:: flake8.utils.normalize_path
+
+This utility takes a string that represents a path and returns the absolute
+path if the string has a ``/`` in it. It also removes trailing ``/``\ s.
+
+.. autofunction:: flake8.utils.normalize_paths
+
+This function utilizes :func:`~flake8.utils.parse_comma_separated_list` and
+:func:`~flake8.utils.normalize_path` to normalize it's input to a list of
+strings that should be paths.
+
+.. autofunction:: flake8.utils.stdin_get_value
+
+This function retrieves and caches the value provided on ``sys.stdin``. This
+allows plugins to use this to retrieve ``stdin`` if necessary.