__init__.py 文件源码

def _process_step(self, step):
        """Steps can be plain strings or tuples when matching images"""
        if isinstance(step, VersionPick):
            # Version pick passed, coerce it ...
            step = step.pick(self.browser.product_version)

        if isinstance(step, tuple):
            image = step[0]
            step = step[1]
            if isinstance(step, VersionPick):
                # Version pick passed, coerce it ...
                step = step.pick(self.browser.product_version)
        else:
            image = None
        if not isinstance(step, six.string_types + (re._pattern_type,)):
            step = str(step)
        return image, step