import pyqtgraph as pg
from pyqtgraph.Qt import QtCore, QtGui
import numpy as np
app = pg.mkQApp()
w = pg.GraphicsLayoutWidget()
p = w.addPlot()
legend = p.addLegend()
legend.setParentItem(p)
for i in range(20):
p.plot(x=range(0,10), y=np.array(range(0,10))*i, name='{0}'.format(i))
w.show()
## Start Qt event loop unless running in interactive mode or using pyside.
if __name__ == '__main__':
import sys
if (sys.flags.interactive != 1) or not hasattr(QtCore, 'PYQT_VERSION'):
QtGui.QApplication.instance().exec_()