new_contents: import json
  from ranch import Address, InvalidAddressException
  
  
  filename = input('Read data from: [data/export.json] ')
  if filename == '':
      filename = 'data/export.json'
  
  with open(filename, 'r') as data:
      specs = json.load(data)
      a = Address(specs)
  
  
  while not a.is_valid():
      fields = a.get_field_types()
  
      last_field = fields[-1]
  
      if len(fields) > 1:
          for field in fields[:-1]:
              if field[0] not in a.fields:
                  last_field = field
                  break
  
      try:
          a.set_field(last_field[0], input(str(last_field[0]) + ': '))
      except InvalidAddressException as e:
          print('Error:', str(e))
  
  print(a)
  
subject: Add a file allowing you to try it manually