remove datatype conversion process that can be skipped

* Add `timeout()` class

* rearrange order

Per VOC empirical results https://github.com/ultralytics/yolov5/issues/3380#issuecomment-853001307 by @developer0hye

* Suppress jit trace warning + graph once

Suppress harmless jit trace warning on TensorBoard add_graph call. Also fix multiple add_graph() calls bug, now only on batch 0.

* Update train.py

* Parse URL authentication

* urllib.parse.unquote()

* improved error handling

* improved error handling

* remove %3F

* update check_file()

* Update README.md

* Changing FLOPS to FLOPs.
Co-authored-by: BuildTools <unconfigured@null.spigotmc.org>

This reverts commit 21a9607e.

Returns `True` if file is part of pip package. Useful for contextual behavior modification.

```python
def is_pip():
    # Is file in a pip package?
    return 'site-packages' in Path(__file__).absolute().parts
```

* COCO evolution fix

* cleanup

* update print

* print fix

* Update datasets.py

* comment
Co-authored-by: Glenn Jocher <glenn.jocher@ultralytics.com>

add Open in Kaggle badge

* Enable direct `--weights URL` definition

@KalenMike this PR will enable direct --weights URL definition. Example use case:
```
python train.py --weights https://storage.googleapis.com/bucket/dir/model.pt
```

* cleanup

* bug fixes

* weights = attempt_download(weights)

* Update experimental.py

* Update hubconf.py

* return bug fix

* comment mirror

* min_bytes

* update ci-testing.yml

* update greetings.yml

* bring back os matrix

* update ci-testing.yml

* update greetings.yml

* bring back os matrix

Fix for https://github.com/ultralytics/yolov5/issues/958#issuecomment-849512083

* Add URL file download to check_file()

* cleanup

* pathlib bug fix

* Update cache v0.2 to include parent hash

Possible fix for https://github.com/ultralytics/yolov5/issues/3349

* Update datasets.py

* `@torch.no_grad()` decorator

* Update detect.py

Add try: except clause on missing requirements install to catch install failures. Prompted by Ultralytics YOLOv5 API failure on Cython.

Ultralytics REST API fix.

* Changing save_one_box 

Made to work with other changes to common.py

* PEP8 and single line BGR
Co-authored-by: Glenn Jocher <glenn.jocher@ultralytics.com>

* adds latest tag to match wandb defaults

* adds entity handling, 'last' tag

* fixes bug causing finished runs to resume

* removes redundant "last" tag for wandb artifact

* YouTube stream ending fix

Properly terminates YouTube streams on video end. Should resolve issues #2769 and #3220.

* Update datasets.py

Bug fix to check batch_size divisibility of utilized CUDA device count vs total system CUDA device count.

* Check CoreML models.train() mode

* Update export.py

Cython required by pycocotools in certain cases, i.e. https://github.com/cocodataset/cocoapi/issues/172

* Color can be none by default

* `plot_one_box()` default `color=(128, 128, 128)`
Co-authored-by: Glenn Jocher <glenn.jocher@ultralytics.com>

* Added max_det parameters in various places

* 120 character line

* PEP8

* 120 character line

* Update inference default to 1000 instances

* Update inference default to 1000 instances
Co-authored-by: Glenn Jocher <glenn.jocher@ultralytics.com>