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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 unit_normal(pt_a, pt_b, pt_c):
 """unit normal vector of plane defined by points pt_a, pt_b, and pt_c"""

    x_val = np.linalg.det([[1, pt_a[1], pt_a[2]], [1, pt_b[1], pt_b[2]], [1, pt_c[1], pt_c[2]]])
    y_val = np.linalg.det([[pt_a[0], 1, pt_a[2]], [pt_b[0], 1, pt_b[2]], [pt_c[0], 1, pt_c[2]]])
    z_val = np.linalg.det([[pt_a[0], pt_a[1], 1], [pt_b[0], pt_b[1], 1], [pt_c[0], pt_c[1], 1]])
    magnitude = (x_val**2 + y_val**2 + z_val**2)**.5
    mag = (x_val/magnitude, y_val/magnitude, z_val/magnitude)
    if magnitude < 0.00000001:
        mag = (0, 0, 0)
    return mag