code: def from_ms_timestamp(ms):
      return pd.to_datetime(ms, unit="ms", utc=True)
  
file_path: catalyst/catalyst/exchange/utils/datetime_utils.py
imports: import calendar
  import math
  import re
  from datetime import datetime, timedelta, date
  import pandas
  import pytz
  from catalyst.exchange.exchange_errors import InvalidHistoryFrequencyError, InvalidHistoryFrequencyAlias
label_desc: Use image node_id 11 for calling a global function with example usage: from_ms_timestamp(ms) and returns: pd