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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 parse_protobuf(self, proto_type):
 """Parse the data into an instance of proto_type."""

        if 'protobuf' not in self.environ.get('CONTENT_TYPE', ''):
            raise BadRequest('Not a Protobuf request')

        obj = proto_type()
        try:
            obj.ParseFromString(self.data)
        except Exception:
            raise BadRequest("Unable to parse Protobuf request")

        # Fail if not all required fields are set
        if self.protobuf_check_initialization and not obj.IsInitialized():
            raise BadRequest("Partial Protobuf request")

        return obj