code: def pandas_dummy_timestamp(pandas_dummy, header):
      time = 1535133442
      time_series = [time + 20 * i for i in range(10)]
      df = pandas_dummy
      df[header["col_timestamp"]] = time_series
      return df
  
file_path: recommenders/contrib/sarplus/python/tests/conftest.py
imports: import calendar
  import datetime
  import pandas
  import pytest
  from sklearn.model_selection import train_test_split
label_desc: Use image node_id 4 for calling a global function with example usage: pandas_dummy_timestamp(pandas_dummy, header) and returns: df