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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 bloch_vector_from_state_vector(state: Sequence, index: int) -> np.ndarray: """Returns the bloch vector of a qubit. Calculates the bloch vector of the qubit at index in the wavefunction given by state, assuming state follows the standard Kronecker convention of numpy.kron. Args: state: A sequence representing a wave function in which the ordering mapping to qubits follows the standard Kronecker convention of numpy.kron. index: index of qubit who's bloch vector we want to find. follows the standard Kronecker convention of numpy.kron. Returns: A length 3 numpy array representing the qubit's bloch vector. Raises: ValueError: if the size of state is not a power of 2. ValueError: if the size of the state represents more than 25 qubits. IndexError: if index is out of range for the number of qubits corresponding to the state. """

    rho = density_matrix_from_state_vector(state, [index])
    v = np.zeros(3, dtype=np.float32)
    v[0] = 2*np.real(rho[0][1])
    v[1] = 2*np.imag(rho[1][0])
    v[2] = np.real(rho[0][0] - rho[1][1])

    return v