To find out the correct date, you need to know the correct timezone. There could be several timezones in the same country. There are databases that allows you to get the timezone from the name of the city e.g., see Get Timezone from City in Python/Django:
#!/usr/bin/env python
from geopy import geocoders # $ pip install geopy
g = geocoders.GoogleV3()
place, (lat, lng) = g.geocode('Tokyo')
timezone = g.timezone((lat, lng)) # return pytz timezone object
print(timezone.zone)
Once you know the timezone, you could use a solution from Change Timezone for Date object Python mentioned by @ILostMySpoon:
#!/usr/bin/env python
import calendar
from datetime import datetime
import pytz # $ pip install pytz
now = datetime.now(pytz.timezone('Asia/Tokyo')) # you could pass `timezone` object here
weekday = now.weekday()
print(calendar.day_name[weekday])