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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 make_gpg_tmphome( prefix=None, config_dir=None ):
 """ Make a temporary directory to hold GPG keys that are not going to be stored to the application's keyring. """

    if prefix is None:
        prefix = "tmp"

    config_dir = get_config_dir( config_dir )
    tmppath = os.path.join( config_dir, "tmp" )
    if not os.path.exists( tmppath ):
        os.makedirs( tmppath, 0700 )

    tmpdir = tempfile.mkdtemp( prefix=("%s-" % prefix), dir=tmppath )
    return tmpdir