def create_docstring(docstring_file_name):
    """
    Instead of using the default header comment a file containing a custom
    on can be used to generate the header comment.
    Args:
        - docstring_file_name (String): Path to the text file containing the
          header comment without comment markers (// or /* */)
    Returns:
        - (String): The header comment specified in the input file enclosed by
          a multi line comment enclosue (/* */)
    """
    lines = ''
    with open(docstring_file_name, 'r') as docstring_file:
        lines = docstring_file.read().split('\n')

    line_max_len = len(max(lines, key=len)) + 1

    docstring = '/* {filler} *\n'.format(filler=line_max_len*'-')
    for line in lines[:-1]:
        docstring += ' * {line} *\n'.format(line=line.ljust(line_max_len))
    docstring += ' * {filler} */\n\n'.format(filler=line_max_len*'-')

    return docstring