code: def cutFrame(self, df):
      lFrameFit = df[self.mEstimStart : self.mEstimEnd]
      lFrameForecast = df[self.mValidStart : self.mValidEnd]
      lFrameTest = df[self.mTestStart : self.mTestEnd]
      return (lFrameFit, lFrameForecast, lFrameTest)
  
file_path: atspy/atspy/TS/TimeSeries_Cutting.py
imports: import pandas
  import numpy
  from .None import Utils
label_desc: Use image node_id 7 for calling the cCuttingInfo obj's underlying member method code with example usage: obj.cutFrame(df) and returns: lFrameFit,  lFrameForecast,  lFrameTest