PyQt - QWidget

import sys
from PyQt4 import QtGui

app = QtGui.QApplication(sys.argv)
widget = QtGui.QWidget()

#widget.resize(400, 300)
widget.setGeometry(200, 100, 400, 300)
widget.setWindowTitle('PyQt Application')
widget.setWindowIcon(QtGui.QIcon('lucia_2d.png'))
widget.setToolTip('Indonesia is a nice one')
widget.setStyleSheet('background: blue')
widget.setWindowStyle(0.5)

widget.show()
sys.exit(app.exec_())

PyQt - QWidget