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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 find_pad_index(self, array):
 """Find padding index. Args: array (list):
 integer list. Returns: idx: padding index. Examples: 2 """

        try:
            return list(array).index(self.pad_value)
        except ValueError:
            return len(array)