Creating a dictionary that writes high scores to a file

I need to make a list of high scores that updates itself upon new entries. So here it goes:

First step - done

I have player-entered input, which has been taken as a data for a few calculations:

import time
import datetime

print "Current time:", time1.strftime("%d.%m.%Y, %H:%M")
time1 = datetime.datetime.now()
a = raw_input("Enter weight: ")    
b = raw_input("Enter height: ")
c = a/b

Second step - making high score list

Here, I would need some sort of a dictionary or a thing that would read the previous entries and check if the score (c) is (at least) better than the score of the last one in "high scores", and if it is, it would prompt you to enter your name.

After you entered your name, it would post your name, your a, b, c, and time in a high score list.

This is what I came up with, and it definitely doesn't work:

list = [("CPU", 200, 100, 2, time1)]
player = "CPU"
a = 200
b = 100
c = 2
time1 = "20.12.2012, 21:38"
list.append((player, a, b, c, time1))
list.sort()

import pickle
scores = open("scores", "w")
pickle.dump(list[-5:], scores)
scores.close()

scores = open("scores", "r")
oldscores = pickle.load(scores)
scores.close()
print oldscores()

I know I did something terribly stupid, but I hope you can help me out with this one.

First, don't use list as a variable name. It shadows the built-in list object. Second, avoid using just plain date strings, since it is much easier to work with datetime objects, which support proper comparisons and easy conversions.

Here is a full example of your code, with individual functions to help divide up the steps. I am trying not to use any more advanced modules or functionality, since you are obviously just learning:

import os
import datetime
import cPickle

# just a constants we can use to define our score file location
SCORES_FILE = "scores.pickle"

def get_user_data():
    time1 = datetime.datetime.now()
    print "Current time:", time1.strftime("%d.%m.%Y, %H:%M")

    a = None
    while True:
        a = raw_input("Enter weight: ")    
        try:
            a = float(a)
        except:
            continue
        else:
            break

    b = None
    while True:
        b = raw_input("Enter height: ")    
        try:
            b = float(b)
        except:
            continue
        else:
            break

    c = a/b

    return ['', a, b, c, time1]

def read_high_scores():
    # initialize an empty score file if it does
    # not exist already, and return an empty list
    if not os.path.isfile(SCORES_FILE):
        write_high_scores([])
        return []

    with open(SCORES_FILE, 'r') as f:
        scores = cPickle.load(f)
    return scores

def write_high_scores(scores):
    with open(SCORES_FILE, 'w') as f:
        cPickle.dump(scores, f)

def update_scores(newScore, highScores):
    # reuse an anonymous function for looking
    # up the `c` (4th item) score from the object
    key = lambda item: item[3]

    # make a local copy of the scores
    highScores = highScores[:]

    lowest = None
    if highScores:
        lowest = min(highScores, key=key)

    # only add the new score if the high scores
    # are empty, or it beats the lowest one
    if lowest is None or (newScore[3] > lowest[3]):
        newScore[0] = raw_input("Enter name: ")
        highScores.append(newScore)

    # take only the highest 5 scores and return them
    highScores.sort(key=key, reverse=True)
    return highScores[:5]

def print_high_scores(scores):
    # loop over scores using enumerate to also
    # get an int counter for printing
    for i, score in enumerate(scores):
        name, a, b, c, time1 = score
        # #1    50.0    jdi    (20.12.2012, 15:02)
        print "#%d\t%s\t%s\t(%s)" % \
            (i+1, c, name, time1.strftime("%d.%m.%Y, %H:%M"))


def main():
    score = get_user_data()
    highScores = read_high_scores()

    highScores = update_scores(score, highScores)

    write_high_scores(highScores)
    print_high_scores(highScores)

if __name__ == "__main__":
    main()

What it does now is only add new scores if there were no high scores or it beats the lowest. You could modify it to always add a new score if there are less than 5 previous scores, instead of requiring it to beat the lowest one. And then just perform the lowest check after the size of highscores >= 5