code: def _store_priors_from_background_dataframe(self, bg_df):
      self.priors += bg_df.reindex(self.priors.index).fillna(0)[
          "background"
      ]
  
imports: import pandas
  import numpy
  from scattertext.termranking import AbsoluteFrequencyRanker
  from scattertext.termsignificance.LogOddsRatioInformativeDirichletPiror import LogOddsRatioInformativeDirichletPrior
label_desc: Use image node_id 4 for calling the PriorFactory obj's underlying member method code with example usage: obj._store_priors_from_background_dataframe(bg_df) without return types