              except StopFutureHandlers:
                  break
  
          for chunk in chunks:
              for i, handler in enumerate(request.upload_handlers):
                  chunk_length = len(chunk)
                  chunk = handler.receive_data_chunk(chunk, counters[i])
                  counters[i] += chunk_length
                  if chunk is None:
                      # If the chunk received by the handler is None, then don't continue.
 
</s> remove         for i, handler in enumerate(request.upload_handlers):
 </s> add         for i, handler in enumerate(upload_handlers): </s> remove         for handler in request.upload_handlers:
 </s> add         for handler in upload_handlers: </s> remove         for handler in request.upload_handlers:
 </s> add         for handler in upload_handlers: </s> remove         possible_sizes = [x.chunk_size for x in request.upload_handlers if x.chunk_size]
 </s> add         possible_sizes = [x.chunk_size for x in upload_handlers if x.chunk_size] </s> remove         counters = [0] * len(request.upload_handlers)
 </s> add         counters = [0] * len(upload_handlers)
            for i, handler in enumerate(upload_handlers):
              except StopFutureHandlers:
                  break
  
          for chunk in chunks:
            for i, handler in enumerate(upload_handlers):
                  chunk_length = len(chunk)
                  chunk = handler.receive_data_chunk(chunk, counters[i])
                  counters[i] += chunk_length
                  if chunk is None:
                      # If the chunk received by the handler is None, then don't continue.
keep keep keep keep replace keep keep keep keep keep
 Codebase improvements on FileUploadParser

* Added docstrings.
* Added `FileUploadParser.get_filename` to make it easier to override.
* Added url kwargs filename detection step.
* Updated tests corresponding to these changes. 
rest_framework/parsers.py