new_contents: 
  class ErrorsDTM(Exception):
      #print "myException"  
      def __init__(self, value):
          print "Error Using DTM Classsss:"
          self.parameter = value
          
  class FrequencyError(ErrorsDTM):
      def __init__(self, value):
          self.parameter = value
          if value<0:
              print "Frequency must be greater than 0, recieved: " + str(value) 
          elif value>39:
              print "Frequency must be less than 39, received: " + str(value) 
          
  
subject: Create ErrorsDTM.py