Update PostgreSQL user credentials using variables in Python - python-3.x

Question

I'm trying to update user credentials for PostgreSQL db user using Python. I've tried referring to the following thread but that doesn't seem to solve my issue unfortunately:
How to change password of a newly created user using variable in postgresql 9.5 SP
Here's my code:
con = p.connect(database="mydB", user="abc", password="testing", host="127.0.0.1", port="5432")
cur = con.cursor()
uid = "adi"
pwd = "test6"
statement = statement = '''CREATE or REPLACE FUNCTION add_user ({}, {}) RETURNS void AS $$ EXECUTE ALTER USER ' || $1 || ' WITH PASSWORD || $2||'''.format(uid,pwd)
cur.execute( statement)
cur.execute('''COMMIT''')
I get the following error:
ProgrammingError: syntax error at or near "'adi'"
Please help or refer me to a thread with a better solution. Thanks in advance, everyone!
error image

Answer 1

I was able to solve this successfully.
import psycopg2 as p
con = p.connect(database="mydB", user="adi", password="xxxx", host="127.0.0.1", port="5432")
cur = con.cursor()
uid = "adi"
pwd = "test"
statement = '''ALTER USER {} WITH PASSWORD %s '''.format(uid)
cur.execute(statement, [pwd])
cur.execute('''COMMIT''')

Answer 2

Try to give the username and password in the actual statement and try executing.
First try removing the extra quotation before ALTER USER and execute.
If doesn't work try this:
statement = '''CREATE or REPLACE FUNCTION add_user ({}, {}) RETURNS void AS $$ EXECUTE 'ALTER USER ' || $1 || ' WITH PASSWORD || $2||'''.format(uid,pwd)
cur.execute(statement)