diff --git a/adafruit_extended_bus.py b/adafruit_extended_bus.py
index 0ee8fbd..295e9dc 100644
--- a/adafruit_extended_bus.py
+++ b/adafruit_extended_bus.py
@@ -59,8 +59,8 @@ class ExtendedI2C(I2C):
         self.deinit()
 
         # Check if the file /dev/i2c-{bus_id} exists and error if not
-        if not path.exists(F"/dev/i2c-{bus_id}"):
-            raise ValueError(F"No device found for /dev/i2c-{bus_id}")
+        if not path.exists(f"/dev/i2c-{bus_id}"):
+            raise ValueError(f"No device found for /dev/i2c-{bus_id}")
         # Attempt to open using _I2C
         self._i2c = _I2C(bus_id, mode=_I2C.MASTER, baudrate=frequency)
 
@@ -90,10 +90,8 @@ class ExtendedSPI(SPI):
         self.deinit()
 
         # Check if the file /dev/i2c-{bus_id} exists and error if not
-        if not path.exists(F"/dev/spidev{bus_id}.{chip_select}"):
-            raise ValueError(
-                F"No device found for /dev/spidev{bus_id}.{chip_select}"
-            )
+        if not path.exists(f"/dev/spidev{bus_id}.{chip_select}"):
+            raise ValueError(f"No device found for /dev/spidev{bus_id}.{chip_select}")
 
         self._spi = _SPI((bus_id, chip_select))
         # Pins aren't used in Linux, so we just use fake pins