NameError: name 'feature' is not defined

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NameError                                 Traceback (most recent call last)
<ipython-input-38-0bb17743e79e> in <module>()
      9 
     10     # Assign the minibatch data to the input variables and train the model on the minibatch
---> 11     trainer.train_minibatch({feature : features, label : labels})
     12     batchsize, loss, error = print_training_progress(trainer, i, 
     13                                                      training_progress_output_freq, verbose=1)

NameError: name 'feature' is not defined