code: def convert_field(self, value, conversion):
          
          func = self.CONV_FUNCS.get(conversion)
          if func is not None:
              value = getattr(value, func)()
          elif conversion not in ['R']:
              # default conversion ('r', 's')
              return super(StringFormatter, self).convert_field(value, conversion)
  
          if conversion in ['h', 'H', 'R']:
              value = value.replace('-', '').replace('_', '').replace(':', '').replace(' ', '')
          return value
docs: Apply conversions mentioned above.