code: def ethinca_order_from_string(order):
      
      if order in get_ethinca_orders().keys():
          return get_ethinca_orders()[order]
      else: raise ValueError("Order "+str(order)+" is not valid for ethinca"
                             "calculation! Valid orders: "+
                             str(get_ethinca_orders().keys()))
docs: Returns the integer giving twice the post-Newtonian order
      used by the ethinca calculation. Currently valid only for TaylorF2 metric
  
      Parameters
      ----------
      order : string
  
      Returns
      -------
      int