def get_expr_vars(operator):
 if (operator.type == lo.VARIABLE):
  return [(operator.data, operator.size)]
 else:
  vars_ = []
  for arg in operator.args:
   vars_ += get_expr_vars(arg)
  return vars_

def get_expr_vars ( operator ) : if ( operator . type == lo . VARIABLE ) : return [ ( operator . data , operator . size ) ] else : vars_ = [ ] for arg in operator . args : vars_ += get_expr_vars ( arg ) return vars_
get a list of the variables in the operator and their sizes .