def add_placeholder(self, placeholder_klass):
        self.placeholders[placeholder_klass.name.upper()] = placeholder_klass()
RF frequency for a given channel.
dataset/ETHPy150Open ellmetha/django-precise-bbcode/precise_bbcode/bbcode/parser.py/BBCodeParser.add_placeholder--crossover with--dataset/ETHPy150Open LabPy/lantz/lantz/drivers/legacy/aa/aotf.py/MDSnC.frequency