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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 returner_argspec(module=''):
    '''
    Return the argument specification of functions in Salt returner
    modules.

    .. versionadded:: 2015.5.0

    CLI Example:

    .. code-block:: bash

        salt '*' sys.returner_argspec xmpp
        salt '*' sys.returner_argspec xmpp smtp
        salt '*' sys.returner_argspec

    Returner names can be specified as globs.

    .. code-block:: bash

        salt '*' sys.returner_argspec 'sqlite3.*'

    '''
    returners_ = salt.loader.returners(__opts__, [])
    return salt.utils.args.argspec_report(returners_, module)