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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 handle_format(self, t, i):
 """Handle format."""


        if t == '{':
            t = self.format_next(i)
            if t == '{':
                self.get_single_stack()
                self.result.append(t)
            else:
                field, text = self.get_format(t, i)
                self.handle_format_group(field, text)
        else:
            t = self.format_next(i)
            if t == '}':
                self.get_single_stack()
                self.result.append(t)
            else:
                raise SyntaxError("Unmatched '}' at %d!" % (i.index - 2))