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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 build_index_name(app, *parts):
 """Build an index name from parts. :param parts: Parts that should be combined to make an index name. """

    base_index = os.path.splitext(
        '-'.join([part for part in parts if part])
    )[0]

    return prefix_index(app=app, index=base_index)