Returns the phase (or angle) of the complex number in radians.

c = Complex<>(1, 1)
print(c.phase())  # Output: 0.7853981633974483 (approximately π/4)

The phase of the complex number in radians. ``` c = Complex<>(1, 1) print(c.phase()) # Output: 0.7853981633974483 (approximately π/4) ```