code: def get_accounts(self, username=None):
          
          url = "{0}/{1}/accounts".format(self.domain, self.API_VERSION)
          params = {"username": username}
          try:
              return self._Client__call(uri=url, params=params, method="get")
          except RequestException:
              return False
          except AssertionError:
              return False
docs: Get a list of accounts owned by the user.
  
              Parameters
              ----------
              username : string
                  The name of the user. Note: This is only required on the
                  sandbox, on production systems your access token will
                  identify you.
  
              See more:
              http://developer.oanda.com/rest-sandbox/accounts/#-a-name-getaccountsforuser-a-get-accounts-for-a-user