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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_local_user():
 """ Return the local executing username, or ``None`` if one can't be found. .. versionadded:: 2.0 """

    # TODO: I don't understand why these lines were added outside the
    # try/except, since presumably it means the attempt at catching ImportError
    # wouldn't work. However, that's how the contributing user committed it.
    # Need an older Windows box to test it out, most likely.
    import getpass

    username = None
    # All Unix and most Windows systems support the getpass module.
    try:
        username = getpass.getuser()
    # Some SaaS platforms raise KeyError, implying there is no real user
    # involved. They get the default value of None.
    except KeyError:
        pass
    # Older (?) Windows systems don't support getpass well; they should
    # have the `win32` module instead.
    except ImportError:  # pragma: nocover
        if win32:
            import win32api
            import win32security  # noqa
            import win32profile  # noqa

            username = win32api.GetUserName()
    return username