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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 strip_context_items(self, a_string):
 """Strip Juniper-specific output. Juniper will also put a configuration context: [edit] and various chassis contexts: {master:0}, {backup:1} This method removes those lines. """

        strings_to_strip = [
            r"\[edit.*\]",
            r"\{master:.*\}",
            r"\{backup:.*\}",
            r"\{line.*\}",
            r"\{primary.*\}",
            r"\{secondary.*\}",
        ]

        response_list = a_string.split(self.RESPONSE_RETURN)
        last_line = response_list[-1]

        for pattern in strings_to_strip:
            if re.search(pattern, last_line):
                return self.RESPONSE_RETURN.join(response_list[:-1])
        return a_string