def get_output_name(output_prefix, namespace, index):
return '<STR_LIT>'.format(output_prefix, namespace, index)<EOL>
Get the output name (prefix)

    Parameters
    ----------
    output_prefix : str
        The path prefix of the target filename

    namespace : str
        The namespace of the annotation in question

    index : int
        The index number of this annotation within the namespace

    Returns
    -------
    output_name : str
        "output_prefix__namespace__index"