Secure way to utilize AWS SSM parameter store to make API call

I need to write a lambda function which makes an API call (to Airflow) using credentials stored in AWS SSM parameter store. I have been supplied with the key id for the credentials.

How can I securely query the credentials and integrate them (again securely) into the API call?

Is this on the right track:

Import boto3

key_supplied = 'the key I was supplied with'
client = boto3.client('ssm')

def lambda_handler(event, context):
     parameter = 
client.get_parameter(Name='key_supplied', WithDecryption=True)
print(parameter)
return parameter ['Parameter']['Value']

I usually have a simple function in such lambda functions:

def get_ssm_param(param: str) -> str:
    session = boto3.session.Session()
    ssm = session.client("ssm")
    return ssm.get_parameter(param, WithDecryption=True)['Parameter']['Value']

Then it can be used as

def lambda_handler(event, context):
    secure_param = get_ssm_param("secure_param_key")
    ...