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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_metadata_file_path(channeldir, filename):
 """ Return the path to the metadata file named `filename` that is a sibling of `channeldir`. """

    channelparentdir, channeldirname = os.path.split(channeldir)
    return os.path.join(channelparentdir, filename)