I'm reading the following piece of code:
[J(C(x, min(f(x).sqrt(0,1)))) for x in (11,22,33)]
where $J$ is the jacobian of my hyper elliptic curve $C$.
I don't undestad what the sqrt function with those two arguments does. Reading from the docs it seems that I'm enabling the all flag:
all - Whether to return a list of all square roots or just a square root (default: False)
Can you explain what is mathematically doing that sqrt?