e^(jx) calculate exact π value.

❄.py

me@amadeus:~$ python3 -q
>>> def exp(x):
...     prod = a = 1
...     for i in range(1, 30):
...             prod *= x/i
...             a += prod
...     return a
... 
>>> x = 1.5
>>> for i in range(3):
...     x += exp(x * 1j).real
... 
>>> 2 * x
3.1415926535897936
>>> 
>>> x = 3
>>> for i in range(3):
...     x += exp(x * 1j).imag
... 
>>> x
3.141592653589793
>>> 
me@amadeus:~$