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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 _simplify_shape(self, alist, rec=0):

 """Reduce the alist dimension if needed"""

        if rec != 0:
            if len(alist) == 1:
                return alist[-1]
            return alist
        if len(alist) == 1:
            return self._simplify_shape(alist[-1], 1)
        return [self._simplify_shape(al, 1) for al in alist]