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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def create_grid(self, grid_width, grid_height):
 """Create a grid layout with stacked widgets. Parameters grid_width : int the width of the grid grid_height : int the height of the grid """

        self.grid_layout = QGridLayout()
        self.setLayout(self.grid_layout)
        self.grid_layout.setSpacing(1)
        self.grid_wgs = {}
        for i in xrange(grid_height):
            for j in xrange(grid_width):
                self.grid_wgs[(i, j)] = FieldWidget()
                self.grid_layout.addWidget(self.grid_wgs[(i, j)], i, j)