code: def get_user(user, flags=FLAGS.ALL, **conn):
      
      user = modify(user, output='camelized')
      _conn_from_args(user, conn)
      return registry.build_out(flags, start_with=user, pass_datastructure=True, **conn)
docs: Orchestrates all the calls required to fully build out an IAM User in the following format:
  
      {
          "Arn": ...,
          "AccessKeys": ...,
          "CreateDate": ...,  # str
          "InlinePolicies": ...,
          "ManagedPolicies": ...,
          "MFADevices": ...,
          "Path": ...,
          "UserId": ...,
          "UserName": ...,
          "SigningCerts": ...
      }
  
      :param user: dict MUST contain the UserName and also a combination of either the ARN or the account_number
      :param output: Determines whether keys should be returned camelized or underscored.
      :param conn: dict containing enough information to make a connection to the desired account.
      Must at least have 'assume_role' key.
      :return: dict containing fully built out user.