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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def applies_to (self, useragent):
 """Check if this entry applies to the specified agent. @return: True if this entry applies to the agent, else False. @rtype: bool """

        if not useragent:
            return True
        useragent = useragent.lower()
        for agent in self.useragents:
            if agent == '*':
                # we have the catch-all agent
                return True
            if agent.lower() in useragent:
                return True
        return False