def get_hk_variable_names(my_df):
    """
    This procedure will return al ist of variables in the
    housekeeping file.

    Parameters
    ----------
    my_df: ACT Dataset
        The dataframe to get the variable names from

    Returns
    -------
    var_names: list
        The names of each variable in the file.
    """
    return [my_str for my_str in my_df.variables.keys()]