The **attrs** and **cattrs** packages version is incompatible.
Check command:
`pip check --use-feature=2020-resolver`

Code file: https://github.com/apache/airflow/blob/master/setup.py
Commit hash: 9150330
Line number:
694: 'attrs~=19.3'
696: 'cattrs~=1.0'

It will caused the final installed **attrs** version is higher than 20.1.0.

Why this happen?
From the dependency setting of **cattrs**:
https://github.com/Tinche/cattrs/blob/master/setup.py
Commit hash: 2f401b9
Line number:
12: "attrs >= 20.1.0"

setup.py
yandexcloud = [
    'yandexcloud>=0.22.0',
]
zendesk = [
    'zdesk',
]
all_dbs = (cassandra + cloudant + druid + exasol + hdfs + hive + mongo + mssql + mysql +
           pinot + postgres + presto + vertica)
devel = [
    'beautifulsoup4~=4.7.1',
    'black',
    'blinker',
    'bowler',
    'click==6.7',
    'contextdecorator;python_version<"3.4"',
    'coverage',
    'docutils',
    'flake8>=3.6.0',
    'flake8-colors',
    'flaky',
    'freezegun',
    'github3.py',
    'gitpython',
    'ipdb',
    'jira',
    'mongomock',
    'moto==1.3.14',  
                     
    'parameterized',
    'paramiko',