code: def setup(self):
      self.rng = period_range(start="1/1/1990", freq="s", periods=20000)
      self.df = DataFrame(index=range(len(self.rng)))
  
imports: from pandas import DataFrame, Period, PeriodIndex, Series, date_range, period_range
  from pandas.tseries.frequencies import to_offset
label_desc: Use image node_id 1 for calling the DataFramePeriodColumn obj's underlying member method code with example usage: obj.setup() without return types