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+
+:mod:`user` --- User-specific configuration hook
+================================================
+
+.. module:: user
+   :synopsis: A standard way to reference user-specific modules.
+
+
+.. index::
+   pair: .pythonrc.py; file
+   triple: user; configuration; file
+
+As a policy, Python doesn't run user-specified code on startup of Python
+programs.  (Only interactive sessions execute the script specified in the
+:envvar:`PYTHONSTARTUP` environment variable if it exists).
+
+However, some programs or sites may find it convenient to allow users to have a
+standard customization file, which gets run when a program requests it.  This
+module implements such a mechanism.  A program that wishes to use the mechanism
+must execute the statement ::
+
+   import user
+
+.. index:: builtin: exec
+
+The :mod:`user` module looks for a file :file:`.pythonrc.py` in the user's home
+directory and if it can be opened, executes it (using :func:`exec`) in its
+own (the module :mod:`user`'s) global namespace.  Errors during this phase are
+not caught; that's up to the program that imports the :mod:`user` module, if it
+wishes.  The home directory is assumed to be named by the :envvar:`HOME`
+environment variable; if this is not set, the current directory is used.
+
+The user's :file:`.pythonrc.py` could conceivably test for ``sys.version`` if it
+wishes to do different things depending on the Python version.
+
+A warning to users: be very conservative in what you place in your
+:file:`.pythonrc.py` file.  Since you don't know which programs will use it,
+changing the behavior of standard modules or functions is generally not a good
+idea.
+
+A suggestion for programmers who wish to use this mechanism: a simple way to let
+users specify options for your package is to have them define variables in their
+:file:`.pythonrc.py` file that you test in your module.  For example, a module
+:mod:`spam` that has a verbosity level can look for a variable
+``user.spam_verbose``, as follows::
+
+   import user
+
+   verbose = bool(getattr(user, "spam_verbose", 0))
+
+(The three-argument form of :func:`getattr` is used in case the user has not
+defined ``spam_verbose`` in their :file:`.pythonrc.py` file.)
+
+Programs with extensive customization needs are better off reading a
+program-specific customization file.
+
+Programs with security or privacy concerns should *not* import this module; a
+user can easily break into a program by placing arbitrary code in the
+:file:`.pythonrc.py` file.
+
+Modules for general use should *not* import this module; it may interfere with
+the operation of the importing program.
+
+
+.. seealso::
+
+   Module :mod:`site`
+      Site-wide customization mechanism.
+