28.15. user — User-specific configuration hook — Python 2.7.18 documentation

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# 28.15. `user` — User-specific configuration hook

Deprecated since version 2.6: The `user` module has been removed in Python 3.

As a policy, Python doesn’t run user-specified code on startup of Python programs. (Only interactive sessions execute the script specified in the `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

The `user` module looks for a file `.pythonrc.py` in the user’s home directory and if it can be opened, executes it (using `execfile()`) in its own (the module `user`’s) global namespace. Errors during this phase are not caught; that’s up to the program that imports the `user` module, if it wishes. The home directory is assumed to be named by the `HOME` environment variable; if this is not set, the current directory is used.

The user’s `.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 `.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 `.pythonrc.py` file that you test in your module. For example, a module `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 `getattr()` is used in case the user has not defined `spam_verbose` in their `.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 `.pythonrc.py` file.

Modules for general use should not import this module; it may interfere with the operation of the importing program.

See also

Module `site`

  Site-wide customization mechanism.