code: def time_frame_period_formatting_custom(self, nobs, freq):
      self.data["p"].dt.strftime(date_format="%Y-%m-%d --- %H:%M:%S")
  
imports: import numpy
  import pandas
  from pandas import offsets
label_desc: Use image node_id 7 for calling the PeriodStrftime obj's underlying member method code with example usage: obj.time_frame_period_formatting_custom(nobs, freq) without return types