def requires(*args):
def wrap(fn):<EOL><INDENT>if None in args:<EOL><INDENT>return nottest(fn)<EOL><DEDENT>return fn<EOL><DEDENT>return wrap<EOL>
Decorator to make test optional based on required user fixtures.

If any of the values in :attr:`*args` are ``None``, then the wrapped test
is considered not-runnable.