(self, db)
return self
gain takes one paramter: gain in dB.
gain takes one paramter: gain in dB.
gain takes one paramter : gain in dB .
def gain(self, db):
        """gain takes one paramter: gain in dB."""
        self.command.append('gain')
        self.command.append(db)
        return self
def gain ( self , db ) : self . command . append ( 'gain' ) self . command . append ( db ) return self