code: def read_datafiles(files, dtype, column):
      '''Load the datafiles and return cov, mag, phase and fpi phase values.
      '''
      pha = []
      pha_fpi = []
      for filename, filetype in zip(files, dtype):
          if filetype == 'cov':
              cov = load_cov(filename)
          elif filetype == 'mag':
              mag = load_rho(filename, column)
          elif filetype == 'pha':
              pha = load_rho(filename, 2)
          elif filetype == 'pha_fpi':
              pha_fpi = load_rho(filename, 2)
  
      return cov, mag, pha, pha_fpf read_datafiles(files, dtype, column):
      '''Load the datafiles and return cov, mag, phase and fpi phase values.
      '''
      pha = []
      pha_fpi = []
      for filename, filetype in zip(files, dtype):
          if filetype == 'cov':
              cov = load_cov(filename)
          elif filetype == 'mag':
              mag = load_rho(filename, column)
          elif filetype == 'pha':
              pha = load_rho(filename, 2)
          elif filetype == 'pha_fpi':
              pha_fpi = load_rho(filename, 2)
  
      return cov, mag, pha, pha_fpi
docs: Load the datafiles and return cov, mag, phase and fpi phase values.