[pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

Author: pre-commit-ci[bot]

Diff for: boolean_algebra/multiplexer.py

@@ -1,5 +1,6 @@
 # https://www.electrically4u.com/solved-problems-on-multiplexer/
 
+
 def mux(input0: int, input1: int, select: int) -> int:
     """
     Implement a 2-to-1 Multiplexer.
@@ -25,6 +26,7 @@ def mux(input0: int, input1: int, select: int) -> int:
     else:
         raise ValueError("Select signal must be 0 or 1")
 
+
 if __name__ == "__main__":
     import doctest