add missing imports

A5/CorrelationFilter.py

@@ -1,4 +1,7 @@
 from sklearn.base import BaseEstimator, TransformerMixin
+import pandas as pd
+import numpy as np
+
 
 # Finds similar features that are highly correlated and remove it
 class CorrelationFilter(BaseEstimator, TransformerMixin):
@@ -8,7 +11,8 @@ class CorrelationFilter(BaseEstimator, TransformerMixin):
 
     def fit(self, X, y=None):
         Xdf = pd.DataFrame(X) if not isinstance(X, pd.DataFrame) else X
-        # calculates the correlation matrix and takes absolutte values since negative values are also calculated
+        # calculates the correlation matrix and takes absolutte values
+        #  since negative values are also calculated
         corr = Xdf.corr(numeric_only=True).abs()
         upper = corr.where(np.triu(np.ones(corr.shape), k=1).astype(bool))
         to_drop = [col for col in upper.columns if any(upper[col] >= self.threshold)]