docs: def loadtxt(fn, **kwargs):
      """Study the text data file fn. Call numpys loadtxt with keyword
      arguments based on the study.
  
      Return data returned from numpy `loadtxt <http://docs.scipy.org/doc/numpy/reference/generated/numpy.loadtxt.html#numpy-loadtxt>`.
  
      kwargs: keyword arguments accepted by numpys loadtxt. Any keyword
      arguments provided will take precedence over the ones resulting
      from the study.
  
      Set the module attribute PP to the instance of PatternPull used.
  
      """
      global PP
      PP = PatternPull(fn)
      txtargs = PP.loadtxtargs()
      txtargs.update(kwargs)      # Let kwargs dominate.
      return np.loadtxt(fn, **txtargs)