I am trying IBM's code for graphing T1 and I keep getting the following error:

ibmqfactory.load_account:WARNING:2020-05-28 12:28:57,538: Credentials are already in use. The existing account in the session will be replaced.
/opt/conda/lib/python3.7/site-packages/qiskit/util.py:109: DeprecationWarning: The QuantumCircuit.iden() method is deprecated as of 0.14.0, and will be removed no earlier than 3 months after that release date. You should use the QuantumCircuit.i() method instead.
  return func(*args, **kwargs)

The link to the code is here: https://quantum-computing.ibm.com/docs/guide/wwwq/decoherence


This is not an error, there are two messages here and they are both just warnings.

The first Credentials are already in use error means that you have called load_account() when you already had an account loaded.

The second message, DeprecationWarning, is letting you know that a method that you are using will be removed in a future version of Qiskit and so it is best to move code over to using a different method. In this case, it means that you need to used .i() instead of .iden()


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