code: def update_ledger(self, ledger_id, description=None):
          
          arguments = {'description': description}
          return self.do_req('PUT',
                             self.merchant_api_base_url + '/ledger/' +
                             ledger_id + '/', arguments)
docs: Update ledger info
  
          Arguments:
              ledger_id:
                  Ledger id assigned by mCASH
              description:
                  Description of the Ledger and it's usage