diff --git a/pyfacts/exceptions.py b/pyfacts/exceptions.py
index 0e5e0ab..dbf0fc8 100644
--- a/pyfacts/exceptions.py
+++ b/pyfacts/exceptions.py
@@ -13,9 +13,9 @@ class DateNotFoundError(Exception):
 class DateOutOfRangeError(Exception):
     """Exception to be raised when provided date is outside the range of dates in the time series"""
 
-    def __init__(self, date: datetime.datetime, type: Literal['min', 'max']) -> None:
-        if type == 'min':
+    def __init__(self, date: datetime.datetime, type: Literal["min", "max"]) -> None:
+        if type == "min":
             message = f"Provided date {date} is before the first date in the TimeSeries"
-        if type == 'max':
+        if type == "max":
             message = f"Provided date {date} is after the last date in the TimeSeries"
         super().__init__(message)