Error when calling cursor.execute with psycopg2 sql.SQL object

I am trying to execute a raw update query using psycopg2 in django. The code is as below:

from django.db import connection
from psycopg2 import sql

model_instances_to_update = []
for model_instance in models_queryset:    
    model_instances_to_update.append(
        sql.Identifier(
            f"({id},{col_1_value},{col_2_value},{col_3_value},{col_4_value})"
        )
    )

model_instance_query_values_string = sql.SQL(", ").join(model_instances_to_update)
model_instance_sql_params = {"updated_model_instance_values": model_instance_query_values_string}

model_instance_update_query = sql.SQL(
    """
    UPDATE {table} AS model_table SET
    col_1 = model_table_new.col_1,
    col_2 = model_table_new.col_2,
    col_3 = model_table_new.col_3,
    col_4 = model_table_new.col_4
    FROM (VALUES (%(updated_model_instance_values)s)) AS model_table_new(id, col_1, col_2, col_3, col_4)
    WHERE model_table.id = model_table_new.id;
    """
).format(
    table=sql.Identifier("table_name"),
)

with connection.cursor() as cursor:
    cursor.execute(
        model_instance_update_query,
        params=model_instance_sql_params,
    )

But when I try to execute this query I am getting the following error:

TypeError: "object of type 'Composed' has no len()"

What am I doing wrong here and how to correct it?

UPDATE I am now passing the list of tuples directly in cursor.execute. I have added placeholders in the SQL object string but I am still getting the same error.

for model_instance in models_queryset:    
    model_instances_to_update.append(
        (
            id,
            col_1_value,
            col_2_value,
            col_3_value,
            col_4_value
        )
    )

model_instance_update_query = sql.SQL(
    """
    UPDATE {table} AS model_table SET
    col_1 = model_table_new.col_1,
    col_2 = model_table_new.col_2,
    col_3 = model_table_new.col_3,
    col_4 = model_table_new.col_4
    FROM (VALUES ({records_list_template})) AS model_table_new(id, col_1, col_2, col_3, col_4)
    WHERE model_table.id = model_table_new.id;
    """
).format(
    table=sql.Identifier("table_name"),
    records_list_template=sql.SQL(",").join(
        [sql.Placeholder()] * len(model_instances_to_update)
    ),
)

with connection.cursor() as cursor:
    cursor.execute(
        model_instance_update_query,
        model_instances_to_update,
    )

UPDATE 2

Below is the output of printing sql from inside execute function.

Composed([SQL('\n        UPDATE '), 
Identifier('table_name'), 
SQL(' AS model_table SET\n        
col_2 = model_table_new.col_2,\n        
col_3 = model_table_new.col_3,\n        
col_4 = model_table_new.col_4,\n        
col_5 = model_table_new.col_5\n        
FROM (VALUES ('), 
Composed([Placeholder(), SQL(', '), Placeholder(), SQL(', '),
Placeholder(), SQL(', '), Placeholder(), SQL(', '),
Placeholder()]), 
SQL(')) AS 
model_table_new(col_1, col_2, col_3, col_4, col_5)\n        
WHERE model_table.id = model_table_new.id;\n        ')])

I tried executing print(model_instance_update_query.as_string(connection)) but I got this error - argument 2 must be connection or cursor. This is because I am using connection object from django.db which is a proxy and not the connection object from psycopg2. So tried as above.