This function will return a random datetime between two datetime objects.

random_date.py

from random import randrange
from datetime import timedelta
from datetime import datetime 
import pytz 

def random_date(start, end):
    """
    This function will return a random datetime between two datetime 
    objects.
    """
    delta = end - start
    int_delta = (delta.days * 24 * 60 * 60) + delta.seconds
    random_second = randrange(int_delta)
    return start + timedelta(seconds=random_second)

local_tz = pytz.timezone('America/Sao_Paulo')
start = local_tz.localize(datetime(2018,5,3), is_dst=None)
end = datetime.utcnow().replace(tzinfo=pytz.utc)

print(random_date(start, end))