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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 uses_na_format(station: str) -> bool: """ Returns True if the station uses the North American format, False if the International format """

    if station[0] in NA_REGIONS:
        return True
    if station[0] in IN_REGIONS:
        return False
    if station[:2] in M_NA_REGIONS:
        return True
    if station[:2] in M_IN_REGIONS:
        return False
    raise BadStation("Station doesn't start with a recognized character set")