code: def make_di_block(dec, inc):
      
      di_block = []
      for n in range(0, len(dec)):
          di_block.append([dec[n], inc[n], 1.0])
      return di_block
docs: Some pmag.py and ipmag.py functions require or will take a list of unit
      vectors [dec,inc,1.] as input. This function takes declination and
      inclination data and make it into such a nest list of lists.
  
      Parameters
      -----------
      dec : list of declinations
      inc : list of inclinations
  
      Returns
      -----------
      di_block : nested list of declination, inclination lists
  
      Example
      -----------
      >>> decs = [180.3, 179.2, 177.2]
      >>> incs = [12.1, 13.7, 11.9]
      >>> ipmag.make_di_block(decs,incs)
      [[180.3, 12.1, 1.0], [179.2, 13.7, 1.0], [177.2, 11.9, 1.0]]