spacerItem = QtWidgets.QSpacerItem(40, 20, QtWidgets.QSizePolicy.Minimum, QtWidgets.QSizePolicy.Expanding)
self.gridlayout.addItem(spacerItem, 1, 6, 1, 1)

void QGridLayout::addWidget(QWidget *widget, int row, int column, Qt::Alignment alignment = Qt::Alignment())

Adds the given widget to the cell grid at row, column. The top-left position is (0, 0) by default.

The alignment is specified by alignment. The default alignment is 0, which means that the widget fills the entire cell.