def merge_headers(headers_1, headers_2):
    """Merge two lists of headers; assumes first column is same in both
    """
    print("Merging: " + str(headers_1))
    print("With: " + str(headers_2))
    if headers_1[0] != headers_2[0]:
        exit("Error: First column of the headers do not match. Aborting!")

    merged_headers = []
    headers_2_without_primary_key = headers_2[1:]

    merged_headers = headers_1 + headers_2_without_primary_key
    print("merged_headers list: " + str(merged_headers))
    return merged_headers