def process_step(self, form):
step = self.steps.current<EOL>self.storage.validated_step_data[step] = form.cleaned_data<EOL>form_list = self.get_form_list()<EOL>keys = list(form_list.keys())<EOL>key = keys.index(step) + <NUM_LIT:1><EOL>for next_step in keys[key:]:<EOL><INDENT>self.storage.validated_step_data.pop(next_step, None)<EOL><DEDENT>return super(IdempotentSessionWizardView, self).process_step(form)<EOL>
Stores the validated data for `form` and cleans out validated forms
for next steps, as those might be affected by the current step. Note
that this behaviour is relied upon by the `LoginView` to prevent users
from bypassing the `TokenForm` by going steps back and changing
credentials.