tests/sitecustomize.py

manifest: document return type of readfast()

I keep having to ponder out what readfast() means, and it always
surprises me. Document the return type in the docstring so that future
readers won't have to puzzle this out again.

import os

if os.environ.get('COVERAGE_PROCESS_START'):
    try:
        import coverage
        import random

        # uuid is better, but not available in Python 2.4.
        covpath = os.path.join(os.environ['COVERAGE_DIR'],
                               'cov.%s' % random.randrange(0, 1000000000000))
        cov = coverage.coverage(data_file=covpath, auto_data=True)
        cov._warn_no_data = False
        cov._warn_unimported_source = False
        cov.start()
    except ImportError:
        pass