docs: def cc_to_local_params(pitch, radius, oligo):
      """Returns local parameters for an oligomeric assembly.
  
      Parameters
      ----------
      pitch : float
          Pitch of assembly
      radius : float
          Radius of assembly
      oligo : int
          Oligomeric state of assembly
  
      Returns
      -------
      pitchloc : float
          Local pitch of assembly (between 2 adjacent component helices)
      rloc : float
          Local radius of assembly
      alphaloc : float
          Local pitch-angle of assembly
      """
      rloc = numpy.sin(numpy.pi / oligo) * radius
      alpha = numpy.arctan((2 * numpy.pi * radius) / pitch)
      alphaloc = numpy.cos((numpy.pi / 2) - ((numpy.pi) / oligo)) * alpha
      pitchloc = (2 * numpy.pi * rloc) / numpy.tan(alphaloc)
      return pitchloc, rloc, numpy.rad2deg(alphaloc)