Improve types coverage in Products module (saleor#4998)

* Add mypy with config and Django stubs

* Types for product utils

* Added types for product utils

* Namedtuple to dataclasses

* WIP VariantPicker

* Better argument name

* Experiment with dataclasses for json structures

* Add type coverage

* More typing

* Review suggestions

* Update requirements files

* Remove duplicates

* Update lock after req rebase

pyproject.toml

@@ -98,6 +98,8 @@ pytest-xdist = "^1.29"
 tox = "^3.13.2"
 transifex-client = "^0"
 yapf = "^0.28"
+django-stubs = "^1.2"
+mypy = "^0.740.0"
 
 [tool.black]
 target_version = ['py35', 'py36', 'py37', 'py38']

requirements.txt

@@ -488,9 +488,9 @@ rx==1.6.1 \
 s3transfer==0.2.1 \
     --hash=sha256:b780f2411b824cb541dbcd2c713d0cb61c7d1bcadae204cdddda2b35cef493ba \
     --hash=sha256:6efc926738a3cd576c2a79725fed9afde92378aa5c6a957e3af010cb019fac9d
-sentry-sdk==0.13.3 \
-    --hash=sha256:e3302e8df82e68599eeeef564f08d15aa62efc1cb013d8e1cccc5bf526d375a4 \
-    --hash=sha256:e795f1744066493f9e1eb3d17e0ee19a042a45789b9edd9f553b8b61bc8d399e
+sentry-sdk==0.13.4 \
+    --hash=sha256:bfc486af718c268cf49ff43d6334ed4db7333ace420240b630acdd8f8a3a8f60 \
+    --hash=sha256:a7c2c8d3f53b6b57454830cd6a4b73d272f1ba91952f59e6545b3cf885f3c22f
 singledispatch==3.4.0.3 \
     --hash=sha256:833b46966687b3de7f438c761ac475213e53b306740f1abfaa86e1d1aae56aa8 \
     --hash=sha256:5b06af87df13818d14f08a028e42f566640aef80805c3b50c5056b086e3c2b9c

requirements_dev.txt

@@ -226,6 +226,9 @@ django-silk==2.0.0 \
 django-storages==1.8 \
     --hash=sha256:9322ab74ba6371e2e0fccc350c741686ade829e43085597b26b07ae8955a0a00 \
     --hash=sha256:0a9b7e620e969fb0797523695329ed223bf540bbfdf6cd163b061fc11dab2d1c
+django-stubs==1.2.0 \
+    --hash=sha256:c0515576de547bb33057e24d1b0294d10a68e55150ee32fc964f1082192ab012 \
+    --hash=sha256:ca565958a66c0772a11bf95e415d0bcd476eb59919a7ed1a417cc93315d68809
 django-templated-email==2.3.0 \
     --hash=sha256:536c4e5ae099eabfb9aab36087d4d7799948c654e73da55a744213d086d5bb33
 django-versatileimagefield==1.11 \
@@ -450,6 +453,24 @@ multidict==4.6.1; python_version >= "3.6" \
     --hash=sha256:87e26d8b89127c25659e962c61a4c655ec7445d19150daea0759516884ecb8b4 \
     --hash=sha256:c626029841ada34c030b94a00c573a0c7575fe66489cde148785b6535397d675 \
     --hash=sha256:5159c4975931a1a78bf6602bbebaa366747fce0a56cb2111f44789d2c45e379f
+mypy==0.740 \
+    --hash=sha256:9371290aa2cad5ad133e4cdc43892778efd13293406f7340b9ffe99d5ec7c1d9 \
+    --hash=sha256:b428f883d2b3fe1d052c630642cc6afddd07d5cd7873da948644508be3b9d4a7 \
+    --hash=sha256:ace6ac1d0f87d4072f05b5468a084a45b4eda970e4d26704f201e06d47ab2990 \
+    --hash=sha256:d7574e283f83c08501607586b3167728c58e8442947e027d2d4c7dcd6d82f453 \
+    --hash=sha256:d5bf0e6ec8ba346a2cf35cb55bf4adfddbc6b6576fcc9e10863daa523e418dbb \
+    --hash=sha256:1521c186a3d200c399bd5573c828ea2db1362af7209b2adb1bb8532cea2fb36f \
+    --hash=sha256:dc889c84241a857c263a2b1cd1121507db7d5b5f5e87e77147097230f374d10b \
+    --hash=sha256:6ed3b9b3fdc7193ea7aca6f3c20549b377a56f28769783a8f27191903a54170f \
+    --hash=sha256:31a046ab040a84a0fc38bc93694876398e62bc9f35eca8ccbf6418b7297f4c00 \
+    --hash=sha256:672e418425d957e276c291930a3921b4a6413204f53fe7c37cad7bc57b9a3391 \
+    --hash=sha256:3b1a411909c84b2ae9b8283b58b48541654b918e8513c20a400bb946aa9111ae \
+    --hash=sha256:540c9caa57a22d0d5d3c69047cc9dd0094d49782603eb03069821b41f9e970e9 \
+    --hash=sha256:f4748697b349f373002656bf32fede706a0e713d67bfdcf04edf39b1f61d46eb \
+    --hash=sha256:48c8bc99380575deb39f5d3400ebb6a8a1cb5cc669bbba4d3bb30f904e0a0e7d
+mypy-extensions==0.4.3 \
+    --hash=sha256:090fedd75945a69ae91ce1303b5824f428daf5a028d2f6ab8a299250a846f15d \
+    --hash=sha256:2d82818f5bb3e369420cb3c4060a7970edba416647068eb4c5343488a6c604a8
 nodeenv==1.3.3 \
     --hash=sha256:ad8259494cf1c9034539f6cced78a1da4840a4b157e23640bc4a0c0546b0cb7a
 oauthlib==3.1.0 \
@@ -697,9 +718,9 @@ rx==1.6.1 \
 s3transfer==0.2.1 \
     --hash=sha256:b780f2411b824cb541dbcd2c713d0cb61c7d1bcadae204cdddda2b35cef493ba \
     --hash=sha256:6efc926738a3cd576c2a79725fed9afde92378aa5c6a957e3af010cb019fac9d
-sentry-sdk==0.13.3 \
-    --hash=sha256:e3302e8df82e68599eeeef564f08d15aa62efc1cb013d8e1cccc5bf526d375a4 \
-    --hash=sha256:e795f1744066493f9e1eb3d17e0ee19a042a45789b9edd9f553b8b61bc8d399e
+sentry-sdk==0.13.4 \
+    --hash=sha256:bfc486af718c268cf49ff43d6334ed4db7333ace420240b630acdd8f8a3a8f60 \
+    --hash=sha256:a7c2c8d3f53b6b57454830cd6a4b73d272f1ba91952f59e6545b3cf885f3c22f
 singledispatch==3.4.0.3 \
     --hash=sha256:833b46966687b3de7f438c761ac475213e53b306740f1abfaa86e1d1aae56aa8 \
     --hash=sha256:5b06af87df13818d14f08a028e42f566640aef80805c3b50c5056b086e3c2b9c
@@ -748,10 +769,35 @@ tqdm==4.39.0 \
 transifex-client==0.12.5 \
     --hash=sha256:23c88c55d1469b62a771646d4f202b6fe5f4abbcdbe61bda3a3b08c44aaa7a78 \
     --hash=sha256:139867ffaf340aa2b74b0c44fa2d6525bf641357d04b7961a5b10ebe468678d8
+typed-ast==1.4.0 \
+    --hash=sha256:262c247a82d005e43b5b7f69aff746370538e176131c32dda9cb0f324d27141e \
+    --hash=sha256:71211d26ffd12d63a83e079ff258ac9d56a1376a25bc80b1cdcdf601b855b90b \
+    --hash=sha256:630968c5cdee51a11c05a30453f8cd65e0cc1d2ad0d9192819df9978984529f4 \
+    --hash=sha256:ffde2fbfad571af120fcbfbbc61c72469e72f550d676c3342492a9dfdefb8f12 \
+    --hash=sha256:4e0b70c6fc4d010f8107726af5fd37921b666f5b31d9331f0bd24ad9a088e631 \
+    --hash=sha256:bc6c7d3fa1325a0c6613512a093bc2a2a15aeec350451cbdf9e1d4bffe3e3233 \
+    --hash=sha256:cc34a6f5b426748a507dd5d1de4c1978f2eb5626d51326e43280941206c209e1 \
+    --hash=sha256:d896919306dd0aa22d0132f62a1b78d11aaf4c9fc5b3410d3c666b818191630a \
+    --hash=sha256:354c16e5babd09f5cb0ee000d54cfa38401d8b8891eefa878ac772f827181a3c \
+    --hash=sha256:95bd11af7eafc16e829af2d3df510cecfd4387f6453355188342c3e79a2ec87a \
+    --hash=sha256:18511a0b3e7922276346bcb47e2ef9f38fb90fd31cb9223eed42c85d1312344e \
+    --hash=sha256:d7c45933b1bdfaf9f36c579671fec15d25b06c8398f113dab64c18ed1adda01d \
+    --hash=sha256:d755f03c1e4a51e9b24d899561fec4ccaf51f210d52abdf8c07ee2849b212a36 \
+    --hash=sha256:2b907eb046d049bcd9892e3076c7a6456c93a25bebfe554e931620c90e6a25b0 \
+    --hash=sha256:fdc1c9bbf79510b76408840e009ed65958feba92a88833cdceecff93ae8fff66 \
+    --hash=sha256:7954560051331d003b4e2b3eb822d9dd2e376fa4f6d98fee32f452f52dd6ebb2 \
+    --hash=sha256:48e5b1e71f25cfdef98b013263a88d7145879fbb2d5185f2a0c79fa7ebbeae47 \
+    --hash=sha256:1170afa46a3799e18b4c977777ce137bb53c7485379d9706af8a59f2ea1aa161 \
+    --hash=sha256:838997f4310012cf2e1ad3803bce2f3402e9ffb71ded61b5ee22617b3a7f6b6e \
+    --hash=sha256:66480f95b8167c9c5c5c87f32cf437d585937970f3fc24386f313a4c97b44e34
 typing==3.7.4.1 \
     --hash=sha256:c8cabb5ab8945cd2f54917be357d134db9cc1eb039e59d1606dc1e60cb1d9d36 \
     --hash=sha256:f38d83c5a7a7086543a0f649564d661859c5146a85775ab90c0d2f93ffaa9714 \
     --hash=sha256:91dfe6f3f706ee8cc32d38edbbf304e9b7583fb37108fef38229617f8b3eba23
+typing-extensions==3.7.4.1 \
+    --hash=sha256:910f4656f54de5993ad9304959ce9bb903f90aadc7c67a0bef07e678014e892d \
+    --hash=sha256:cf8b63fedea4d89bab840ecbb93e75578af28f76f66c35889bd7065f5af88575 \
+    --hash=sha256:091ecc894d5e908ac75209f10d5b4f118fbdb2eb1ede6a63544054bb1edb41f2
 urllib3==1.25.7 \
     --hash=sha256:a8a318824cc77d1fd4b2bec2ded92646630d7fe8619497b142c84a9e6f5a7293 \
     --hash=sha256:f3c5fd51747d450d4dcf6f923c81f78f811aab8205fda64b0aba34a4e48b0745