This is especially (or only?) useful for testing purposes.

The value 0 does not mean "read all", but literally "read nothing". A
value of 512 should be enough to read a couple of urls.

There's no need for this, as long as the tests are invoked as

    python -m pytest

The passed parameter was being ignored.

This seems to happen when the body is empty.

This is required so that setuptools's find_packages can find the
plugins.