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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 output(self, attrs=None, header="Set-Cookie:", sep="\015\012"):
 """Return a string suitable for HTTP."""

        result = []
        items = sorted(self.items())
        for key, value in items:
            result.append(value.output(attrs, header))
        return sep.join(result)