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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_uuid_string(low=None, high=None, **x):
 """This method parses a UUID protobuf message type from its component 'high' and 'low' longs into a standard formatted UUID string Args: x (dict):
 containing keys, 'low' and 'high' corresponding to the UUID protobuf message type Returns: str: UUID formatted string """

    if low is None or high is None:
        return None
    x = ''.join([parse_part(low), parse_part(high)])
    return '-'.join([x[:8], x[8:12], x[12:16], x[16:20], x[20:32]])