from pandas import DataFrame, Series

def signals(data: DataFrame) -> Series:
    """
    Calculate the End of Month (EOM) signal.
    Returns a Series with 'L' for long signals if the date is close to the end of the month and 'N' otherwise.
    """
    return data['Date'].apply(lambda x: 'L' if x.day in [23, 24, 25, 26, 27] else 'N')