class_docstr: Transforms the input sentence by removing a subordinate clause.
  
  Example::
  
      original: "The bill intends to restrict the RTC to
          Treasury borrowings only, unless the agency receives
          specific congressional authorization."
      transformed: "The bill intends to restrict the RTC to
          Treasury borrowings only."
code: def get_difference(num_pair):
      assert num_pair[0] < num_pair[1]
      return num_pair[1] - num_pair[0]
  
imports: from ..transformation import Transformation
label_desc: Use image node_id 4 for calling the DeleteSubTree obj's underlying member method code with example usage: obj.get_difference(num_pair) and returns: unknown