from cryptography.hazmat.primitives import hashes
from cryptography.hazmat.primitives.asymmetric import ec
from timeit import default_timer as timer
import math

# cryptography should be installed already. If not run the following: 
#> pip install cryptography


private_key = ec.generate_private_key(
    ec.SECP192R1()
)

data = b"Hello World!"

start = timer()
signature = private_key.sign(
    data,
    ec.ECDSA(hashes.SHA256())
)
duration = timer() - start

print("Duration: %f" % duration)
print("Size private_key: %d" % (math.ceil(private_key.key_size/8)))
print("Size public_key: %d" % (math.ceil(private_key.public_key().key_size/8)))
print("Size signature: %d" % len(signature))