statistics are empty

from tenacity import *

@retry(stop=stop_after_attempt(3))
def raise_my_exception():
    raise Exception("Fail")

try:
    raise_my_exception()
except Exception as e:
    print(e)
    pass

print(raise_my_exception.retry.statistics)

RetryError[<Future at 0x7ffb5b7902d0 state=finished raised Exception>]
{}

{ "attempt_number" : 3 }