def dict_to_cfn_params(cfn_params_dict):
    """Convert a dictionary to a list of CloudFormation params."""
    if cfn_params_dict:
        cfn_params = []
        for cfn_key, cfn_value in cfn_params_dict.items():
            cfn_params.append({"ParameterKey": cfn_key, "ParameterValue": cfn_value})
    else:
        cfn_params = None
    return cfn_params