from sklearn.base import BaseEstimator, TransformerMixin


class FeatureSelector( BaseEstimator, TransformerMixin ):
    #Class Constructor 
    def __init__( self, feature_names ):
        self._feature_names = feature_names 
    
    #Return self nothing else to do here    
    def fit( self, X, y = None ):
        return self 
    
    #Method that describes what we need this transformer to do
    def transform( self, X, y = None ):
        return X[ self._feature_names ] 
