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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 is_mobile_number_portable_region(region_code):
 """Returns true if the supplied region supports mobile number portability. Returns false for invalid, unknown or regions that don't support mobile number portability. Arguments: region_code -- the region for which we want to know whether it supports mobile number portability or not. """

    metadata = PhoneMetadata.metadata_for_region(region_code, None)
    if metadata is None:
        return False
    return metadata.mobile_number_portable_region