Removing flask dependency

[gleb-sevruk]

While trying to get rid of flask, I stumbled upon aiohttp+socket.io. dependency graph looks as:

Warning!!! Possibly conflicting dependencies found:
* twine==1.14.0
 - requests [required: >=2.5.0,!=2.16,!=2.15, installed: ?]
 - readme-renderer [required: >=21.0, installed: ?]
* requests-toolbelt==0.9.1
 - requests [required: >=2.0.1,<3.0.0, installed: ?]
------------------------------------------------------------------------
aiohttp==3.6.0
  - async-timeout [required: >=3.0,<4.0, installed: 3.0.1]
  - attrs [required: >=17.3.0, installed: 19.1.0]
  - chardet [required: >=2.0,<4.0, installed: 3.0.4]
  - idna-ssl [required: >=1.0, installed: 1.1.0]
    - idna [required: >=2.0, installed: 2.8]
  - multidict [required: >=4.0,<5.0, installed: 4.5.2]
  - typing-extensions [required: >=3.6.5, installed: 3.7.4]
  - yarl [required: >=1.0,<2.0, installed: 1.3.0]
    - idna [required: >=2.0, installed: 2.8]
    - multidict [required: >=4.0, installed: 4.5.2]
argh==0.26.2
coverage==4.5.3
dnspython==1.16.0
docutils==0.15.2
monotonic==1.5
pathtools==0.1.2
pip-autoremove==0.9.1
pipdeptree==0.13.2
  - pip [required: >=6.0.0, installed: 19.0.3]
pydevd-pycharm==193.2956.40
pytest==4.6.3
  - atomicwrites [required: >=1.0, installed: 1.3.0]
  - attrs [required: >=17.4.0, installed: 19.1.0]
  - importlib-metadata [required: >=0.12, installed: 0.23]
    - zipp [required: >=0.5, installed: 0.5.1]
  - more-itertools [required: >=4.0.0, installed: 7.0.0]
  - packaging [required: Any, installed: 19.0]
    - pyparsing [required: >=2.0.2, installed: 2.4.0]
    - six [required: Any, installed: 1.12.0]
  - pluggy [required: >=0.12,<1.0, installed: 0.12.0]
    - importlib-metadata [required: >=0.12, installed: 0.23]
      - zipp [required: >=0.5, installed: 0.5.1]
  - py [required: >=1.5.0, installed: 1.8.0]
  - six [required: >=1.10.0, installed: 1.12.0]
  - wcwidth [required: Any, installed: 0.1.7]
python-socketio==4.3.1
  - python-engineio [required: >=3.9.0, installed: 3.9.3]
    - six [required: >=1.9.0, installed: 1.12.0]
  - six [required: >=1.9.0, installed: 1.12.0]
PyYAML==5.1
twine==1.14.0
  - pkginfo [required: >=1.4.2, installed: 1.5.0.1]
  - readme-renderer [required: >=21.0, installed: ?]
  - requests [required: >=2.5.0,!=2.16,!=2.15, installed: ?]
  - requests-toolbelt [required: >=0.8.0,!=0.9.0, installed: 0.9.1]
    - requests [required: >=2.0.1,<3.0.0, installed: ?]
  - setuptools [required: >=0.7.0, installed: 40.8.0]
  - tqdm [required: >=4.14, installed: 4.35.0]
urllib3==1.25.3
watchgod==0.4
wheel==0.33.4