Invalid specifier: '>=3.6:'

[kfuku52]

With python 3.9, I got the following error with python setup.py install when installing the latest SubPhaser.

> python setup.py install
error in subphaser setup command: 'python_requires' must be a string containing valid version specifiers; Invalid specifier: '>=3.6:'

The installation worked well after replacing python_requires='>=3.6:' with python_requires='>=3.6' in setup.py.

[zhangrengang]

Ok, I will fix it for compatibility. Thank you.