# codes_6.py

class MyForm(QtGui.QWidget):

def __init__(self):

super().__init__()

self.init_GUI()

def init_GUI(self):

# Creating the grid that will position Widgets in a matrix

# like manner

grid = QtGui.QGridLayout()

self.setLayout(grid)

values = ['1', '2', '3',

'4', '5', '6',

'7', '8', '9',

'*', '0', '#']

positions = [(i, j) for i in range(4) for j in range(3)]

for _positions, value in zip(positions, values):

if value == '':

continue

# The * symbol allows unpacking _positions as

# independent arguments

button = QtGui.QPushButton(value)

grid.addWidget(button, *_positions)

self.move(300, 150)

self.setWindowTitle('Calculator')

self.show()