Questions: Checkpoint 3 — Data Wrangler

Start with word = "wizardry". Use one print(...) call with one f-string to combine the first character (word[0]), the last character (word[-1]), the slice word[2:5], and the reversed word (word[::-1]).

Start with phrase = " Hello, Data World! ". Build cleaned = phrase.strip().lower().replace(",", ""). Then print the result of "data" in cleaned as a True/False value.

Start with scores = [88, 92, 75]. Append 100 to scores, then print the first score (scores[0]) and the last score (scores[-1]).

Start with scores = [88, 92, 75, 100]. Use a loop to print each score. Then print len(scores), max(scores), and min(scores). Finally, start total at 0, use another loop over the integers in scores to add each score to total, and print total. Do not calculate an average.

Start with scores = [88, 92, 75, 100]. Sort scores in place by calling scores.sort(reverse=True). Then print the top three scores using indexes [0], [1], and [2].

Start with prices = {"apple": 3, "pear": 2}. Print prices["pear"], print prices.get("fig", 0), and print the True/False result of "apple" in prices.

Next, write a three-way branch using membership tests only. If "plum" in prices, print its price. Otherwise, use elif to check whether "pear" in prices and print its price. In the else branch, print "sold out".

Start with words = ["cat","dog","cat","bird","cat"] and counts = {}. Use exactly one loop over words to build the counts. Inside that loop, if word in counts, use counts[word] = counts[word] + 1; otherwise, use counts[word] = 1.

After the counting loop, use a loop over counts.items() to print each word and its count.

This code crashes when it tries to look up a missing price:

prices = {"apple": 3}
print(prices["fig"])

Here is the actual traceback from running that code:

Traceback (most recent call last):
  File "checkpoint.py", line 2, in <module>
    print(prices["fig"])
          ~~~~~~^^^^^^^
KeyError: 'fig'

First read the traceback from the bottom up. In a comment in your answer cell, write the error name and missing key. Then rewrite the code safely using the dictionary method you learned so a missing "fig" price becomes 0, and print that price without crashing.