usdt.functions.approve(lending_pair.address, deposit_amount).transact({'from': w3.eth.accounts[0]})
lending_pair.functions.deposit(w3.eth.accounts[0], usdt.address, deposit_amount).transact({'from': w3.eth.accounts[0]})
  Error: Transaction reverted: function returned an unexpected amount of data
      at LendingPair._safeTransferFrom (contracts/TransferHelper.sol:20)
      at LendingPair.deposit (contracts/LendingPair.sol:95)
