diff --git a/common.py b/common.py
index 422cfc9..1637161 100644
--- a/common.py
+++ b/common.py
@@ -1,4 +1,4 @@
-from typing import Dict, List, Tuple
+from typing import Dict, List, Tuple, Union
 
 import matplotlib.pyplot as plt
 import numpy as np
@@ -33,7 +33,7 @@ city_coords: Dict = {
 }
 
 
-def plot_plan(city_order: List[str]) -> None:
+def plot_plan(city_order: Union[List[str], npt.NDArray]) -> None:
     """A function that plots the circuit given by city_order.
 
     This function was given in the assignment from 2024.