fix format issue

.pre-commit-config.yaml

@@ -1,6 +1,6 @@
 repos:
   - repo: https://github.com/ambv/black
-    rev: 20.8b1
+    rev: 22.1.0
     hooks:
       - id: black
         exclude: ".virtual_documents"

mufs/Selection.py

@@ -128,7 +128,7 @@ class MUFS:
         k = len(features)
         for pair in list(combinations(features, 2)):
             rff += self._compute_su_features(*pair)
-        return k * rcf / sqrt(k + (k ** 2 - k) * rff)
+        return k * rcf / sqrt(k + (k**2 - k) * rff)
 
     def cfs(self, X, y):
         """Correlation-based Feature Selection