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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 compute_dr_wrt(self,wrt):
 """Default method for objects that just contain a number or ndarray"""

        if wrt is self: # special base case  
            return sp.eye(self.x.size, self.x.size)
            #return np.array([[1]])
        return None