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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 update(self, request, id):
 """Update an object."""

        try:
            object = self.model.objects.get(id=id)
        except self.model.DoesNotExist:
            return self._render(
                request = request,
                template = '404',
                context = {
                    'error': 'The %s could not be found.' % self.model.__name__.lower()
                },
                status = 404,
                prefix_template_path = False
            )

        fields = []
        for field in request.PATCH:

            try:
                self.model._meta.get_field_by_name(field)
            except FieldDoesNotExist:
                continue
            else:
                fields.append(field)

        Form = generate_form(
            model = self.model,
            form = self.form,
            fields = fields
        )

        form = Form(request.PATCH, instance=object)
        if form.is_valid():
            object = form.save()

            return self.show(request, id)
        else:
            return self._render(
                request = request,
                template = 'edit',
                context = {
                    'form': form
                },
                status = 400
            )