Step_2 and Step_3 train/test_model Function Redefinition

[RoboEvangelist]

Folks,

In Step_2 train/test_model functions have four (4) outputs. In Step_3 train/test_model functions have two (2) outputs. Yet, there is only one _mini_batch() function definition in train_functions.py. That unique function is expecting four (4) outputs, and is causing GPU memory fragmentation when _mini_batch() is called on Step_3