import re


def entry_valid(entry):
    """ Checks if a spreadsheet entry for a day is valid, meaning it has all
        fields filled in a way that makes sense """

    if len(entry) != 4:
        return False
    date_list = re.split('\\W', entry[0])
    if len(date_list) != 2:
        return False
    try:
        int(date_list[0])
        int(date_list[1])
        float(entry[2])
    except ValueError:
        return False
    return True