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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 single_qubit_matrix_to_gates( mat: np.ndarray, tolerance: float = 0 ) -> List[ops.SingleQubitGate]: """Implements a single-qubit operation with few gates. Args: mat: The 2x2 unitary matrix of the operation to implement. tolerance: A limit on the amount of error introduced by the construction. Returns: A list of gates that, when applied in order, perform the desired operation. """

    rotations = single_qubit_matrix_to_pauli_rotations(mat, tolerance)
    return [cast(ops.SingleQubitGate, pauli)**ht for pauli, ht in rotations]