input: Write a python function to get the day of the week from a date string in the format 'mm/dd/yyyy'.
  assert get_weekday('3/22/2021') == 'Monday'
  assert get_weekday('12/25/2020') == 'Friday'
  assert get_weekday('7/4/2022') == 'Monday'
output: def get_weekday(date_string):
      from datetime import datetime
      days = ["Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday"]
      date_object = datetime.strptime(date_string, '%m/%d/%Y')
      return days[date_object.weekday()]