import re


def get_spot_analysis(dated_lines, pattern_spot):
    """Return the list of the dates when the event is matching the pattern."""

    spot_analysis = [] # [ <datetime> ]
    pattern_spot_re = re.compile(pattern_spot)

    for d, data, original_line in dated_lines:
        if pattern_spot_re.search(data):
            spot_analysis.append(d)

    return spot_analysis