def extract_features(row):
    """ extract_features function

    Taking one row, extracts all features deemed useful for logistic regression
    and returns them as a list.

    Args
    ----
    row : dict
        A single data point

    Returns
    -------
    list
    """
    pclass = float(row['Pclass']) if row['Pclass'] != '' else 0
    sex = 1 if row['Sex'] == 'male' else 0
    age = float(row['Age']) if row['Age'] != '' else 0
    sibsp = float(row['SibSp']) if row['SibSp'] != '' else 0
    parch = float(row['Parch']) if row['Parch'] != '' else 0

    return [pclass, sex, age, sibsp, parch]