<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def matches_address(self, address):
 """returns whether this account knows about an email address :param str address: address to look up :rtype: bool """

        if self.address == address:
            return True
        for alias in self.aliases:
            if alias == address:
                return True
        if self._alias_regexp and self._alias_regexp.match(address):
            return True
        return False