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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 _check_valid_data(self, data):
 """Checks that the incoming data is a Nx1 ndarray. Parameters data : :obj:`numpy.ndarray` The data to verify. Raises ------ ValueError If the data is not of the correct shape or if the vector is not normed. """

        if len(data.shape) == 2 and data.shape[1] != 1:
            raise ValueError('Can only initialize Direction from a single Nx1 array') 
        if np.abs(np.linalg.norm(data) - 1.0) > 1e-4:
            raise ValueError('Direction data must have norm=1.0')