use of : in subElement on python

Question

I hope you are doing well guys.

I am creating a XML file using python, I am not an expert, but so far I think I am doing fine. During the creation of a subelement I ran to the next issue.

I created a subelement named AP and then inside also I created the subelement named adr, inside Adr I need to create another subelement with the name of S, the complication came when I tried to add the attribute with :, as shown I need to create the next code with the structure "xsi:type", my code is as shown bellow:

AP= et.SubElement(root, 'AP')
adr= et.SubElement(AP, 'Adr')
et.SubElement(adr, 'S',type="num", **'xsi=:type=number').text = str(reles['num_exel'][0])
et.SubElement(adr, 'S',type="str", **'xsi=:type=street').text = str(reles['str_exel'][0])

the goal is to have something similar to the next XML structure

<Adr>
<S type="num" xsi:type="number">10</P>
<S type="str" xsi:type="street">linton</P>
</Adr>

I hope its clear, and I will appreciate your help Thanks a lot