def findSubnetAcl(subnet_id, acls):
    """
    Method that returns the acl assigned to the specified subnet

        Parameters:
            subnet_id (str): The ID of the subnet
            acls (obj): The ACLs of a VPC

        Returns:
            acl (obj): The ACL assigned to the subnet
    """
    for acl in acls:
        for association in acl["Associations"]:
            if association["SubnetId"] == subnet_id:
                return acl
    return None