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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 cache_dir(path, saltenv='base', include_empty=False, include_pat=None,
              exclude_pat=None):
    '''
    Download and cache everything under a directory from the master


    include_pat : None
        Glob or regex to narrow down the files cached from the given path. If
        matching with a regex, the regex must be prefixed with ``E@``,
        otherwise the expression will be interpreted as a glob.

        .. versionadded:: 2014.7.0

    exclude_pat : None
        Glob or regex to exclude certain files from being cached from the given
        path. If matching with a regex, the regex must be prefixed with ``E@``,
        otherwise the expression will be interpreted as a glob.

        .. note::

            If used with ``include_pat``, files matching this pattern will be
            excluded from the subset of files defined by ``include_pat``.

        .. versionadded:: 2014.7.0


    CLI Examples:

    .. code-block:: bash

        salt '*' cp.cache_dir salt://path/to/dir
        salt '*' cp.cache_dir salt://path/to/dir include_pat='E@*.py$'
    '''
    return _client().cache_dir(
        path, saltenv, include_empty, include_pat, exclude_pat
    )