requirements.txt check failed

Nobody has claimed this yet.

When I was doing `pip install -r requirements.txt` I got, specifying hashes will break the install each time there is any update of a pypi dependency.

```
THESE PACKAGES DO NOT MATCH THE HASHES FROM THE REQUIREMENTS FILE. If you have updated the package versions, please update the hashes. Otherwise, examine the package contents carefully; someone may have tampere
d with them.
cffi==1.11.5 from https://files.pythonhosted.org/packages/51/7b/d1014289d0578c3522b2798b9cb87c65e5b36798bd3ae68a75fa1fe09e78/cffi-1.11.5-cp37-cp37m-manylinux1_x86_64.whl#sha256=a6a5cb8809091ec9ac03edde9304b
3ad82ad4466333432b16d78ef40e0cce0d5 (from -r requirements.txt (line 9)):
Expected sha256 151b7eefd035c56b2b2e1eb9963c90c6302dc15fbd8c1c0a83a163ff2c7d7743
Expected or 1553d1e99f035ace1c0544050622b7bc963374a00c467edafac50ad7bd276aef
Expected or 1b0493c091a1898f1136e3f4f991a784437fac3673780ff9de3bcf46c80b6b50
Expected or 2ba8a45822b7aee805ab49abfe7eec16b90587f7f26df20c71dd89e45a97076f
Expected or 3c85641778460581c42924384f5e68076d724ceac0f267d66c757f7535069c93
Expected or 3eb6434197633b7748cea30bf0ba9f66727cdce45117a712b29a443943733257
Expected or 4c91af6e967c2015729d3e69c2e51d92f9898c330d6a851bf8f121236f3defd3
Expected or 770f3782b31f50b68627e22f91cb182c48c47c02eb405fd689472aa7b7aa16dc
Expected or 79f9b6f7c46ae1f8ded75f68cf8ad50e5729ed4d590c74840471fc2823457d04
Expected or 7a33145e04d44ce95bcd71e522b478d282ad0eafaf34fe1ec5bbd73e662f22b6
Expected or 857959354ae3a6fa3da6651b966d13b0a8bed6bbc87a0de7b38a549db1d2a359
Expected or 87f37fe5130574ff76c17cab61e7d2538a16f843bb7bca8ebbc4b12de3078596
Expected or 95d5251e4b5ca00061f9d9f3d6fe537247e145a8524ae9fd30a2f8fbce993b5b
Expected or 9d1d3e63a4afdc29bd76ce6aa9d58c771cd1599fbba8cf5057e7860b203710dd
Expected or a36c5c154f9d42ec176e6e620cb0dd275744aa1d804786a71ac37dc3661a5e95
Expected or ae5e35a2c189d397b91034642cb0eab0e346f776ec2eb44a49a459e6615d6e2e
Expected or b0f7d4a3df8f06cf49f9f121bead236e328074de6449866515cea4907bbc63d6
Expected or b75110fb114fa366b29a027d0c9be3709579602ae111ff61674d28c93606acca
Expected or ba5e697569f84b13640c9e193170e89c13c6244c24400fc57e88724ef610cd31
Expected or be2a9b390f77fd7676d80bc3cdc4f8edb940d8c198ed2d8c0be1319018c778e1
Expected or d5d8555d9bfc3f02385c1c37e9f998e2011f0db4f90e250e5bc0c0a85a813085
Expected or e55e22ac0a30023426564b1059b035973ec82186ddddbac867078435801c7801
Expected or e90f17980e6ab0f3c2f3730e56d1fe9bcba1891eeea58966e89d352492cc74f4
Expected or ecbb7b01409e9b782df5ded849c178a0aa7c906cf8c5a67368047daab282b184
Expected or ed01918d545a38998bfa5902c7c00e0fee90e957ce036a4000a88e3fe2264917
Expected or edabd457cd23a02965166026fd9bfd196f4324fe6032e866d0f3bd0301cd486f
Expected or fdf1c1dc5bafc32bc5d08b054f94d659422b05aba244d6be4ddc1c72d9aa70fb
Got a6a5cb8809091ec9ac03edde9304b3ad82ad4466333432b16d78ef40e0cce0d5
```

PS : I have the same issue with the updated requirements.txt

Open requirements.txt and inspect the cffi==1.11.5 entry identified as line 9; compare its recorded hashes with the artifact pip downloads. Re-run pip install -r requirements.txt and confirm installation succeeds without a hash mismatch, with the corrected requirements file included as done.

Written by the indexing model from the issue text.