Helper function to convert string to list.
     Used to convert shape attribute string to list format.

def convert_string_to_list(string_val):
    """Helper function to convert string to list.
     Used to convert shape attribute string to list format.
    """
    result_list = []

    list_string = string_val.split(',')
    for val in list_string:
        val = str(val.strip())
        val = val.replace("(", "")
        val = val.replace(")", "")
        val = val.replace("L", "")
        val = val.replace("[", "")
        val = val.replace("]", "")
        if val not in ("", "None"):
            result_list.append(int(val))

    return result_list