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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 _opening_bracket_index(self, text, bpair=('(', ')')):
 """Return the index of the opening bracket that matches the closing bracket at the end of the text."""

        level = 1
        for i, char in enumerate(reversed(text[:-1])):
            if char == bpair[1]:
                level += 1
            elif char == bpair[0]:
                level -= 1
            if level == 0:
                return len(text) - i - 2