I feel the simplest way would be
from matplotlib import pyplot;
from pylab import genfromtxt;
mat0 = genfromtxt("data0.txt");
mat1 = genfromtxt("data1.txt");
pyplot.plot(mat0[:,0], mat0[:,1], label = "data0");
pyplot.plot(mat1[:,0], mat1[:,1], label = "data1");
pyplot.legend();
pyplot.show();