# Write a context manager which temporarily replaces
# sys.stdout with a io.StringIO() object and thus
# captures the output of print().

import contextlib

@contextlib.contextmanager
def capture_stdout():
    r"""Replace sys.stdout with String() for the block.

    >>> with capture_stdout() as out:
    ...     print('goo')
    >>> out.getvalue()
    'goo\n'
    """
    try:
        yield ...
    finally:
        pass

# To test this file, use:
#  py.test-3.4 --doctest-modules capture_stdout.py
# or
#  python3 -m doctest capture_stdout.py