LoginForm and SignupForm for Django apps

forms.py

#-*- coding: utf-8 -*-

from django import forms
from models import User

class PasswordField(forms.CharField):
	def __init__(self):
		super(PasswordField, self).__init__(widget=forms.PasswordInput)

class LoginForm(forms.Form):
	username = forms.CharField()
	password = PasswordField()
	
	def clean_username(self):
		username = self.cleaned_data['username']
		try:
			User.objects.get(username=username)
		except User.DoesNotExist:
			raise forms.ValidationError('User name is not registered')
		return username
	
	def clean_password(self):
		password = self.cleaned_data['password']
		user = User.objects.get(username=self.cleaned_data['username'])
		if not user.check_password(password):
			raise forms.ValidationError('Passwords do not match')
		return password

class SignupForm(forms.Form):
	username = forms.CharField()
	first_name = forms.CharField()
	last_name = forms.CharField(required=False)
	email = forms.EmailField()
	password = PasswordField()
	confirm_password = PasswordField()
	
	def clean_username(self):
		username = self.cleaned_data['username']
		try:
			User.objects.get(username=username)
		except User.DoesNotExist:
			pass
		else:
			raise forms.ValidationError('User name already registered')
		return username
	
	def clean_email(self):
		email = self.cleaned_data['email']
		try:
			User.objects.get(email=email)
		except User.DoesNotExist:
			pass
		else:
			raise forms.ValidationError('User already registered with this e-mail address')
		return email
	
	def clean_confirm_password(self):
		password = self.cleaned_data['password']
		confirm_password = self.cleaned_data['confirm_password']
		if password != confirm_password:
			raise forms.ValidationError('Passwords do not match')
		return confirm_password