As per the [docstring standard](https://github.com/numpy/numpy/blob/master/doc/HOWTO_DOCUMENT.rst.txt) we are following:

> The length of docstring lines should be kept to 75 characters to facilitate reading the docstrings in text terminals.

Also this is fairly verbose for a description of what it does. Usually we use an imperative, like

> Apply the constraint represented by this object to a given tensor, along the specified axes.