code: def belowma(f, c, p=50):
      r"""Determine those values of the dataframe that are below the
      moving average.
  
      Parameters
      ----------
      f : pandas.DataFrame
          Dataframe containing the column ``c``.
      c : str
          Name of the column in the dataframe ``f``.
      p : int
          The period of the moving average.
  
      Returns
      -------
      new_column : pandas.Series (bool)
          The array containing the new feature.
  
      """
      new_column = f[c] < ma(f, c, p)
      return new_column
  
imports: from alphapy.calendrical import biz_day_month
  from alphapy.calendrical import biz_day_week
  from alphapy.globals import NULLTEXT
  from alphapy.globals import BSEP, PSEP, USEP
  from alphapy.variables import vexec
  import itertools
  import logging
  import math
  import numpy
  import pandas
label_desc: Use image node_id 3 for calling a global function with example usage: belowma(f, c, p) and returns: new_column