Recommended command recurses into my virtualenv

[adamchainz]

Is your feature request related to a problem? Please describe.
I ran the recommended command in usage, djcodemod run --deprecated-in 3.0 . . I wondered how there were 10k files to modify before realizing it's recursing into my virtualenv and rewriting everything there.

Describe the solution you'd like
A minimal solution would be to say not recommend . as the path.

A more complete solution would be to check if a folder looks like a virtualenv (e.g. has a "bin/activate") before recursing into it.

Additional context
n/a

[browniebroke]

Right... I agree that -at least- the documentation should be updated to not recomment .. I'm not sure about guessing exclusion rules, though.

Someone also mentioned an option to exclude some folders #264 which could default to a list of common things which should be excluded. The --exclude option from black would probably be a good starting point.