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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 update_pos(self, pos_id, name, pos_type, location=None):
 """Update POS resource. Returns the raw response object. Arguments: pos_id: POS id as chosen on registration name: Human-readable name of the POS, used for displaying payment request origin to end user pos_type: POS type location: Merchant location """

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