code: def set_max_freq(self, max_freq=None):
          
          if max_freq:
              self['max_freq'] = max_freq
          else:
              for frequency in self['frequencies']:
                  if self['max_freq']:
                      if frequency['value'] > self['max_freq']:
                          self['max_freq'] = frequency['value']
                  else:
                      self['max_freq'] = frequency['value']
          return
docs: Set the max frequency for the variant
  
              If max_freq use this, otherwise go through all frequencies and
              set the highest as self['max_freq']
  
              Args:
                  max_freq (float): The max frequency