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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 _create_B(self,Y):
 """ Creates OLS coefficient matrix Parameters Y : np.array The dependent variables Y Returns The coefficient matrix B """
         

        Z = self._create_Z(Y)
        return np.dot(np.dot(Y,np.transpose(Z)),np.linalg.inv(np.dot(Z,np.transpose(Z))))