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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 _set_config_defaults(self, request, form, obj=None):
 """ Cycle through app_config_values and sets the form value according to the options in the current apphook config. self.app_config_values is a dictionary containing config options as keys, form fields as values:: app_config_values = { 'apphook_config': 'form_field', } :param request: request object :param form: model form for the current model :param obj: current object :return: form with defaults set """

        for config_option, field in self.app_config_values.items():
            if field in form.base_fields:
                form.base_fields[field].initial = self.get_config_data(request, obj, config_option)
        return form