code: def get_property_values(self, property_name):
          '''
          Returns all property values for a particular property name in this collection
          '''
          property_values = set()
          for signature_value in self.values():
              if signature_value.get(property_name):
                  property_values.add(signature_value[property_name])
          return property_valuef get_property_values(self, property_name):
          '''
          Returns all property values for a particular property name in this collection
          '''
          property_values = set()
          for signature_value in self.values():
              if signature_value.get(property_name):
                  property_values.add(signature_value[property_name])
          return property_values
docs: Returns all property values for a particular property name in this collection