A prism in code

You will write three functions for a prism. All angles are in degrees.

The idea. A ray with angle of incidence $i$ meets a prism of angle $A$ and index $n$. Snell's law gives $r_1$ at the first face. Then $r_2 = A - r_1$. Snell's law again gives the angle $e$ at the second face, and $\delta = i + e - A$. At minimum deviation, $n = \dfrac{\sin\frac{A + \delta_m}{2}}{\sin\frac{A}{2}}$. Python's math.sin needs radian, so change with math.radians and math.degrees.

Your tasks.

1. In deviation, return the angle of deviation for a ray with angle of incidence i.
2. In minimum_deviation, return the smallest deviation from $A$ and $n$.
3. In refractive_index, return $n$ from $A$ and the minimum deviation delta_m.