Hotel/hotel/rooms/forms.py

from django.forms import ModelForm
from django.utils.translation import gettext_lazy as _
from .models import *


class ClientForm(ModelForm):

    class Meta:

        model = Client
        fields = '__all__'
        labels = {
            'id_number': _('Numer dowodu '),
            'name': _('Imię '),
            'surname': _('Nazwisko ')
        }

    def __init__(self, *args, **kwargs):
        super(ClientForm, self).__init__(*args, **kwargs)
        self.fields['id_number'].error_messages = {'required': 'custom required message'}