How to check form field value for specific values?

Question

Django

Good afternoon!
I check in forms.py the validity of the values ​​entered by the user.

class chooses_log(forms.Form):
    channel = forms.CharField(required=True,  min_length=3, max_length=10)
    date    = forms.DateField(input_formats=['%Y/%m/%d'])
    page    = forms.IntegerField(required=True, min_value=1, max_value=1000)

In the channel field, there are three options that the user can choose from. How to check these values? Can this be done without validators?
To make it clearer, a user on the site clicks on a link, let's say support, the GET parameter channel=support comes to the view, we create a variable with the form, pass GET parameters to it and then check the validity of form.is_valid(), and so, as in the channel field check that the value matches 'support' or two other values. otherwise return False.

Answer 1

return channel if channel in ['support', 'second', 'third'] else False

?