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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 to_multiregion(region):
 """Convert a single region or multiple region specification into multiregion list. If a single region (chrom, start, end), returns [(chrom, start, end)] otherwise returns multiregion. """

    assert isinstance(region, (list, tuple)), region
    if isinstance(region[0], (list, tuple)):
        return region
    else:
        assert len(region) == 3
        return [tuple(region)]