sklearn mahalanobis distance
In [18]: import numpy as np
In [19]: from sklearn.datasets import make_classification
In [20]: from sklearn.neighbors import DistanceMetric
In [21]: X, y = make_classification()
In [22]: DistanceMetric.get_metric('mahalanobis', V=np.cov(X))
Out[22]: <sklearn.neighbors.dist_metrics.MahalanobisDistance at 0x107aefa58>