code: def set_proxy(self, proxy_account, account=None, **kwargs):
          
          if not account:
              if "default_account" in self.config:
                  account = self.config["default_account"]
          if not account:
              raise ValueError("You need to provide an account")
          account = Account(account, blockchain_instance=self)
          proxy = Account(proxy_account, blockchain_instance=self)
          options = account["options"]
          options["voting_account"] = proxy["id"]
  
          op = operations.Account_update(
              **{
                  "fee": {"amount": 0, "asset_id": "1.3.0"},
                  "account": account["id"],
                  "new_options": options,
                  "extensions": {},
                  "prefix": self.prefix,
              }
          )
          return self.finalizeOp(op, account["name"], "active", **kwargs)
docs: Set a specific proxy for account
  
              :param bitshares.account.Account proxy_account: Account to be
                      proxied
              :param str account: (optional) the account to allow access
                  to (defaults to ``default_account``)