code: def plotForecasts(self, df):
      lPrefix = self.mSignal + "_"
      lTime = self.mTimeInfo.mNormalizedTimeColumn
      tsplot.decomp_plot(
          df,
          lTime,
          lPrefix + "Signal",
          lPrefix + "Forecast",
          lPrefix + "Residue",
      )
  
imports: import pandas
  import numpy
  from .None import PredictionIntervals
  from .None import Plots
  from .None import Perf
  from .None import Utils
label_desc: Use image node_id 13 for calling the cTimeSeriesModel obj's underlying member method code with example usage: obj.plotForecasts(df) without return types