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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 _getCommonStart(self, left, right):
 """ Return the common prefix of the 2 strings. @param left: one string @param right: another string """

        prefix = []
        for a, b in zip(left, right):
            if a == b:
                prefix.append(a)
            else:
                break

        return ''.join(prefix)