One PlotDataItem can Cointains Multiple Curves?.

[Rajab Legnain]

Hello
In pyqtgraph docoment, it says that one plotDataItem object can have multiple curves. I tried to implemented but it did not work.

here is the code 

import pyqtgraph as pg
from pyqtgraph.Qt import QtCore, QtGui
import numpy as np

pg.setConfigOption('background', 'w')

pg.mkQApp()
pw = pg.PlotWidget()


pw.show()
p1 = pw.plotItem

c = pg.PlotCurveItem([{'x': [1,2,3], 'y': [11,22,33]}, {'x': [1,2,3], 'y': [11,22,33]}])
p1.addItem(c)


if __name__ == '__main__':
    import sys
    if (sys.flags.interactive != 1) or not hasattr(QtCore, 'PYQT_VERSION'):
        QtGui.QApplication.instance().exec_()