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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def post(self, *args, **kwargs):
 """ This method handles POST requests. The wizard will render either the current step (if form validation wasn't successful), the next step (if the current step was stored successful) or the done view (if no more steps are available) """

        # Look for a wizard_prev_step element in the posted data which
        # contains a valid step name. If one was found, render the requested
        # form. (This makes stepping back a lot easier).
        wizard_prev_step = self.request.POST.get('wizard_prev_step', None)
        if wizard_prev_step and wizard_prev_step in self.get_form_list():
            self.storage.current_step = wizard_prev_step
            form = self.get_form(
                data=self.storage.get_step_data(self.steps.current),
                files=self.storage.get_step_files(self.steps.current))
            return self.render(form)

        # Check if form was refreshed
        management_form = ManagementForm(self.request.POST, prefix=self.prefix)
        if not management_form.is_valid():
            raise ValidationError(
                'ManagementForm data is missing or has been tampered.')

        form_current_step = management_form.cleaned_data['current_step']
        if (form_current_step != self.steps.current and
                self.storage.current_step is not None):
            # form refreshed, change current step
            self.storage.current_step = form_current_step

        # get the form for the current step
        form = self.get_form(data=self.request.POST, files=self.request.FILES)

        # and try to validate
        if form.is_valid():
            # if the form is valid, store the cleaned data and files.
            self.storage.set_step_data(self.steps.current, self.process_step(form))
            self.storage.set_step_files(self.steps.current, self.process_step_files(form))

            # check if the current step is the last step
            if self.steps.current == self.steps.last:
                # no more steps, render done view
                return self.render_done(form, **kwargs)
            else:
                # proceed to the next step
                return self.render_next_step(form)
        return self.render(form)