  import warnings
  
  from django.forms.utils import flatatt, pretty_name
  from django.forms.widgets import Textarea, TextInput
  from django.utils import six
  from django.utils.deprecation import RemovedInDjango21Warning
  from django.utils.encoding import force_text
  from django.utils.functional import cached_property
  from django.utils.html import conditional_escape, format_html, html_safe
  from django.utils.inspect import func_supports_parameter
 
</s> remove from django.utils import six
 </s> add  </s> remove from django.utils import six
 </s> add  </s> remove from django.utils import lru_cache, six
 </s> add from django.utils import lru_cache </s> remove from django.utils.six import string_types, text_type
 </s> add  </s> remove from django.utils import six
 </s> add 
  import warnings
  
  from django.forms.utils import flatatt, pretty_name
  from django.forms.widgets import Textarea, TextInput

  from django.utils.deprecation import RemovedInDjango21Warning
  from django.utils.encoding import force_text
  from django.utils.functional import cached_property
  from django.utils.html import conditional_escape, format_html, html_safe
  from django.utils.inspect import func_supports_parameter
keep keep keep keep replace keep keep keep keep keep
 Refs #23919 -- Removed six.<various>_types usage

Thanks Tim Graham and Simon Charette for the reviews. 
django/forms/boundfield.py