          'invalid_choice': '`{input}` is not a valid choice.'
      }
      coerce_to_type = str
  
      def __init__(self, *args, **kwargs):
          choices = kwargs.pop('choices')
  
          assert choices, '`choices` argument is required and may not be empty'
  
          # Allow either single or paired choices style:
 
</s> remove     def __init__(self, *args, **kwargs):
 </s> add     def __init__(self, **kwargs): </s> remove         super(CharField, self).__init__(*args, **kwargs)
 </s> add         self.max_length = kwargs.pop('max_length', None)
        self.min_length = kwargs.pop('min_length', None)
        super(CharField, self).__init__(**kwargs) </s> remove             # if model_field.help_text is not None:
            #     kwargs['help_text'] = model_field.help_text
 </s> add             #  if model_field.help_text is not None:
            #      kwargs['help_text'] = model_field.help_text </s> remove                  label=None, style=None):
 </s> add                  label=None, style=None, error_messages=None): </s> remove     #_hyperlink_field_class = HyperlinkedRelatedField
    #_hyperlink_identify_field_class = HyperlinkedIdentityField
 </s> add     # _hyperlink_field_class = HyperlinkedRelatedField
    # _hyperlink_identify_field_class = HyperlinkedIdentityField
    def __init__(self, **kwargs):
          'invalid_choice': '`{input}` is not a valid choice.'
      }
      coerce_to_type = str
  
    def __init__(self, **kwargs):
          choices = kwargs.pop('choices')
  
          assert choices, '`choices` argument is required and may not be empty'
  
          # Allow either single or paired choices style:
keep keep keep keep replace keep keep keep keep keep
 Add relations and get tests running 
rest_framework/fields.py