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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 create_pos(self, name, pos_type, pos_id, location=None):
 """Create POS resource Arguments: name: Human-readable name of the POS, used for displaying payment request origin to end user pos_type: POS type location: Merchant location pos_id: The ID of the POS that is to be created. Has to be unique for the merchant """

        arguments = {'name': name,
                     'type': pos_type,
                     'id': pos_id,
                     'location': location}
        return self.do_req('POST', self.merchant_api_base_url + '/pos/', arguments).json()