'Create a L{File} that when opened for reading, returns a L{StringIO}.
@return: 2-tuple of the opened "file" and the L{File}.
@rtype: L{tuple}'

def _makeFilePathWithStringIO(self):

    fakeFile = StringIO()
    path = FilePath(self.mktemp())
    path.touch()
    file = static.File(path.path)
    file.open = (lambda : fakeFile)
    return (fakeFile, file)
