["python","requirements.txt"]
In requirements.txt, what does tilde equals (~=) mean?

In the requirements.txt for a Python library I am using, one of the requirements is specified like: mock-django~=0.6.10 What does ~= mean?
It means it will select the latest version of the package, greater than or equal to 0.6.10, but still in the 0.6.* version, so it won't download 0.7.0 for example. It ensures you will get security fixes but keep backward-compatibility, if the package maintainer respects the semantic versioning (which states that breaking changes should occur only in major versions). Or, as said by PEP 440: For a given release identifier V.N , the compatible release clause is approximately equivalent to the pair of comparison clauses: >= V.N, == V.* Definition in PEP 440 Complete example here in the documentation