ssh provider has limit to sshtunnel  < 0.2
https://github.com/apache/airflow/blob/9d6ae609b60449bd274c2f96e72486d73ad2b8f9/setup.py#L451

I don't know why? sshtunnel  already released 0.4
I didn't open PR because I don't know this provider i just tried to install it and couldn't due to conflicts with other requirements in my system so eventually i used vitrual env to solve my problem but logging this issue so that someone who knows this code can handle it.
setup.py
'aws_xray_sdk',
    'beautifulsoup4~=4.7.1',
    'black',
    'blinker',
    'bowler',
    'click>=7.1,<9',
    'coverage',
    'filelock',
    'flake8>=3.6.0',
    'flake8-colors',
    'flaky',
    'freezegun',
    'github3.py',
    'gitpython',
    'ipdb',
    'jira',
    'jsondiff',
    'mongomock',
    'moto~=2.2, >=2.2.7',
    'mypy==0.770',
    'parameterized',
    'paramiko',
    'pipdeptree',
    'pre-commit',
    'pypsrp',
    'pygithub',
    'pysftp',
    'pytest~=6.0',
    'pytest-asyncio',
    'pytest-cov',