code: def get_controller_ctor(controller_name):
      """Returns the constructor for a givn controller name."""
      if controller_name == "LSTM":
          return recurrent.LSTM
      elif controller_name == "GRU":
          return recurrent.GRU
      else:
          # References for other controllers can be added here
          return getattr(sys.modules[__name__], controller_name)
  
file_path: sonnet/sonnet/src/nets/dnc/control.py
imports: import sys
  from sonnet.src import linear
  from sonnet.src import recurrent
  import tensorflow
label_desc: Use image node_id 1 for calling a global function with example usage: get_controller_ctor(controller_name) and returns: recurrent, recurrent, getattr