docs: def _set_elangles(self):
          """Sets the values of instance variable elangles.
          
          Method creates a dictionary containing the elangles of the pvol file.
          Elangles are ordered in acending order using uppercase letters as keys
          
          Examples
          --------
          >>> pvol = OdimPVOL('pvol.h5')
          >>> print(pvol.elangles)
          {'A': 0.5, 'C': 1.5, 'B': 0.69999999999999996, 'E': 5.0, 'D': 3.0}
          """
          elang_list = list(self.attr_gen('elangle'))
          try:
              elevation_angles = sorted(zip(*elang_list)[1])
              n_elangles = len(elevation_angles)
              self.elangles = dict(zip(list(string.ascii_uppercase[:n_elangles]), elevation_angles))
          except IndexError:
              self.elangles = {}