def temp_column_name(*dataframes):
    """Gets a temp column name that isn't included in columns of any dataframes

    Parameters
    ----------
    dataframes : list of Pandas.DataFrame
        The DataFrames to create a temporary column name for

    Returns
    -------
    str
        String column name that looks like '_temp_x' for some integer x
    """
    i = 0
    while True:
        temp_column = "_temp_{}".format(i)
        unique = True
        for dataframe in dataframes:
            if temp_column in dataframe.columns:
                i += 1
                unique = False
        if unique:
            return temp_column