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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 call(self, phone_number, message, message_type, **params):
 """ Send a voice call to the target phone_number. See https://developer.telesign.com/docs/voice-api for detailed API documentation. """

        return self.post(VOICE_RESOURCE,
                         phone_number=phone_number,
                         message=message,
                         message_type=message_type,
                         **params)