def dimer_true(dataframe, col_num, dimer_list):
    """
    Boolean masks to let us know which primers from original df
    form dimers. If so they are dropped.
    Args:
        dataframe (pd.DataFrame): the primer dataframe
        col_num (int): the column number to check for primer match
        dimer_list (list): the list containing primer dimer info
    Returns:
        out_series (pd.Series): boolean masked series, True if primer is dimer, else False
    """
    out_series = dataframe.iloc[:, col_num].isin([seq[1] or seq[2] for seq in dimer_list])
    return out_series