def get_pd_row_index(df, value, column_name):
    """
    Returns pandas row index (label) for a row with a specific value in a specific column
    :param df: pandas dataframe
    :param value: specific value
    :param column_name: specific column
    :return: row index (label)
    """
    index = df.index
    idx_matches = index[df[column_name] == value].tolist()
    if len(idx_matches) == 1:
        return idx_matches[0]

    return None