def get_wait_time(authenticated):
    """Get the wait time based on whether EUtils API use is autheticated or not.

    Parameters
    ----------
    authenticated : bool
        Whether EUtils API use is authenticated.

    Returns
    -------
    float
        Wait time to use between API calls, in seconds.

    Notes
    -----
    The wait time for requesting is set for the E-Utils API, which allows for:
    - 10 requests/second for authenticated users (using an API key)
    - 3 requests/second otherwise
    More information on rate limits is availabe here: https://www.ncbi.nlm.nih.gov/books/NBK25497/
    """
    return 1 / 10 if authenticated else 1 / 3
