Creating a simple GUI application using PyQt involves the following steps −

• Import QtGui module.

• Create an application object.

• A QWidget object creates top level window. Add QLabel object in it.

• Set the caption of label as “hello world”.

• Define the size and position of window by setGeometry() method.

• Enter the mainloop of application by app.exec_() method.

import sys
from PyQt4 import QtGui

def window():
   app = QtGui.QApplication(sys.argv)
   w = QtGui.QWidget()
   b = QtGui.QLabel(w)
   b.setText("Hello World!")
   w.setGeometry(100,100,200,50)
   b.move(50,20)
   w.setWindowTitle(“PyQt”)
   w.show()
   sys.exit(app.exec_())
	
if __name__ == ''__main__'':
   window()

The above code produces the following output −