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class myform(QtGui.QMainWindow):

    def __init__(self, parent=None):

        super(myform, self).__init__(parent)

        self.ui = Ui_mygui()
        self.ui.setupUi(self)

        self.ui.mytablewidget.cellClicked.connect(self.cell_was_clicked)

    @QtCore.pyqtSlot() # prevents executing following function twice
    def cell_was_clicked(self):
        row = self.ui.mytablewidget.currentItem().row()
        print "row=",row
        col = self.ui.mytablewidget.currentItem().column()
        print "col=",col
        item = self.ui.mytablewidget.horizontalHeaderItem(col).text()
        print "item=",item

#===================================================================
# given a tablewidget which has a selected row...
# return the column value in the same row which corresponds to a given column name
# fyi: columnname is case sensitive
#===================================================================

def getsamerowcell(widget,columnname):

    row = widget.currentItem().row()
    #col = widget.currentItem().column()

    #loop through headers and find column number for given column name
    headercount = widget.columnCount()
    for x in range(0,headercount,1):
        headertext = widget.horizontalHeaderItem(x).text()
        if columnname == headertext:
            cell = widget.item(row, x).text()   # get cell at row, col
            return cell