django update string value with using existing value

it's possible to use F queries to make updates with using existing values in database, it's quite easy if value is number but
when you want to do updates on string values things are getting complicated  a bit

Here below I am replacing empty char coming after comma in location field such as


London, UK


We need to use django's special functions for this purpose F Value and Func

from django.db.models import F, Func, Value
Developer.objects.filter(location__contains=", ").update(location=Func(
        F('location'),
        Value(', '), Value(','),
        function='replace',
    ))


Result will be

London,UK

which is our intended solution

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