serializers.py

class UserSerializer(ModelSerializer):

    password = CharField(style={'input_type': 'password'}, write_only=True)
    password2 = CharField(style={'input_type': 'password'}, write_only=True)

    class Meta:
        model = get_user_model()
        fields = ('id', 'username', 'password', 'password2',
                  'email', 'first_name', 'last_name',)
        extra_kwargs = {
            'first_name': {'required': True},
            'last_name': {'required': True},
            'password': {'write_only': True},
            'password2': {'write_only': True},
        }

    def create(self, validated_data):
        '''
        Override the create method of this to create user
        '''
        user = get_user_model().objects.create(
            username=validated_data['username'],
            email=validated_data['email'],
            first_name=validated_data['first_name'],
            last_name=validated_data['last_name']
        )

        # validate password and set password
        user.set_password(validated_data['password'])
        

        user.save()
        return user