Python: Retrieving "NULL" from nested(!) dictionary when key is missing

I’m processing some data that comes from nested dictionaries (over an API).
I want to store the data into a database, I use psycopg2 to do so and I wrote some code to put together my SQL statements (“INSERT INTO mytable…”).

Everything runs fine so far, but every now and then the data does not have all the required information. In rare cases one of the keys is missing. This causes my script to crash.
So I tried some kind of error handling, because in the case of missing data, I just want to have “NULL” instead.

But, I only got it to work when I repeated the “try/except block” for every single piece of data. Isn’t there an easier way to do this?

Here’s an example:

mydict = {'name': {'firstname': 'Peter', 'surname': 'Pan'}, 'contact': {'hometown': 'Neverland', 'phone': '123-456'}}

sql = f"INSERT INTO mytable(firstname, surname, phone)\nVALUES\n("
sql += f"'{mydict['name']['firstname']}',"
sql += f"'{mydict['name']['surname']}',"
sql += f"'{mydict['contact']['phone']}');"

For the case of missing data I tried:

mydict = {'name': {'firstname': 'Peter', 'surname': 'Pan'}, 'contact': {'hometown': 'Neverland'}}

sql = f"INSERT INTO mytable(firstname, surname, phone)\nVALUES\n("
try:
    sql += f"'{mydict['name']['firstname']}',"
except KeyError:
    sql += 'NULL'
try:
    sql += f"'{mydict['name']['surname']}',"
except KeyError:
    sql += 'NULL'
try:
    sql += f"'{mydict['contact']['phone']}');"
except KeyError:
    sql += f"NULL);"

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