:mod:`user` --- User-specific configuration hook

.. module:: user
   :synopsis: A standard way to reference user-specific modules.
   :deprecated:

.. deprecated:: 2.6
   The :mod:`user` module has been removed in Python 3.

.. 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: execfile

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:`execfile`) 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.