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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 data(self, buffer_index):
 """Return the data vector for a given ring buffer"""

        # Check for expired elements and discard if they exist
        expired = self.time - self.max_time     
        exp = self.buffer_expire[buffer_index]
        j = 0
        while j < len(exp):
            # Everything before this j must be expired
            if exp[j] >= expired:
                self.buffer_expire[buffer_index] = exp[j:].copy()
                self.buffer[buffer_index] = self.buffer[buffer_index][j:].copy()
                break
            j += 1
       
        return self.buffer[buffer_index]