PyQT - Make integers and dates in QTableWidget properly sortable

[NewPyQt]

Hi.
I put the data into my QTableWidget tableView using a loop:

for i in range(0, len(res)):
                self.tableView.setItem(i, 2, QTableWidgetItem(str(create_dataframe(res)[2][i])))
                self.tableView.setItem(i, 3, QTableWidgetItem(str(create_dataframe(res)[3][i])))

for i in range(0, len(res)):
                self.tableView.setItem(i, 2, QTableWidgetItem(str(create_dataframe(res)[2][i])))
                self.tableView.setItem(i, 3, QTableWidgetItem(str(create_dataframe(res)[3][i])))

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where

create_dataframe(res)[2][i]

create_dataframe(res)[2][i]

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returns value of class 'int' and

create_dataframe(res)[3][i]

create_dataframe(res)[3][i]

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returns value of class 'datetime.datetime' (like '2017-03-25 16:51:24'). The question is: how do I make this items properly sortable through

self.tableView.setSortingEnabled(True)

self.tableView.setSortingEnabled(True)

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, i.e. not as strings, but as integers and datetime respectively? I know that I should use setData and Qt.DisplayRole, but could you please give an example using this short piece of code?
Thank you.