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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 __GetRequestField(self, method_description, body_type):
 """Determine the request field for this method."""

        body_field_name = self.__BodyFieldName(body_type)
        if body_field_name in method_description.get('parameters', {}):
            body_field_name = self.__names.FieldName(
                '%s_resource' % body_field_name)
        # It's exceedingly unlikely that we'd get two name collisions, which
        # means it's bound to happen at some point.
        while body_field_name in method_description.get('parameters', {}):
            body_field_name = self.__names.FieldName(
                '%s_body' % body_field_name)
        return body_field_name