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Lab 13 — Strings, Part 3

In this lab you will gain some additional practice with strings. Start by downloading Write all your code in

Emoji Replace

Write a function called emoji_replace(sentence). This function takes one parameter:

  • sentence: a string

The function returns a new string that replaces each of the following strings with its corresponding emoji:

  • 'fire' with '\U0001F525'
  • 'love' with '\u2764'
  • 'birthday' with '\U0001F382'
  • 'plane' with '\U00002708'

Note that this should not operate on words but strings, so planet will still have plane replaced with its corresponding emoji.

You should use the str.replace() function discussed in lecture.

Emoji Word Replace

Write a function called emoji_word_replace(sentence). It does the same thing as above, but only replaces complete words. So planet will remain planet and only plane will be replaced with its corresponding emoji.

You should use str.split() to convert the sentence into words. Now you will have a list of words you can cycle through, and you can replace items in the list directly, since lists are mutable. For example:

for index in range(len(words)):
    if words[index] == 'hello':
        words[index] = 'goodbye'

Once you have the list of new words setup, you can turn them back into a string using str.join().

To keep things simple, we will not worry about punctuation for this function.

Stock Trades

This is a repeat of a problem from Lab 9, except you will use str.split() to make your job easier. You are given a file with trades of GameStop shares, using the following format:


For example, the file might contain:


Total Trades

Write a function called total_trades(filename). It takes one parameter:

  • filename: the name of a file containing trades for the NYSE stock Gamestop (GME)

The function determines the total number of shares bought and sold. For example:

>>> total_trades('gamestop_trades.txt')
3 shares bought
30 shares sold

You can use str.split() to split each line as you loop through the lines in the file. Remember, you may want to use strip() to remove the trailing newline from the end of a line. You can do this with:

line = line.strip()

Reminder: Remember you will need to convert string values to integer values when you want to sum integers.

Market Manipulators

Often, when a single entity or group of entities decide to sell a large amount of stock at once, the price of that stock falls. With the rise in automated trading, concerns arise over large groups taking advantage of this trend and dumping stock to deliberately tank a stock price.

Write a function called find_percent_seller(filename, entity_name). It takes two parameters:

  • filename: the name of a file containing trades for the NYSE stock Gamestop (GME)
  • entity_name: the name of an entity in this data set

The function calculates the percentage of stock sold by the named entity. For example:

>>> find_percent_seller('gamestop_trades.txt', 'KAREL_CO')
KAREL_CO sold 70.0 percent of GME stock sold

The percentages for the doctests are rounded to two decimal places. You can do this with the round() function:

percent = round(percent, 2)

Uppercase Words

Write a function called uppercase_words(sentence, letter). This function takes two parameters:

  • sentence: a string
  • letter: a single character

The function finds every word that starts with the given letter and changes that word to uppercase. The rest of the words are unchanged. The function returns a new string that is the same as the original string but with some words in uppercase.

You will want to use the same pattern for this function — use str.split() to get the words, loop through the list to change words, and then join them back together again.

Uppercase Many Words

Write a function called capitalize_many_words(sentence, letters). This function works the same as above, except the letters parameter is a string. The function returns a new string that is the same as the original string, but any word that starts with any of the letters in letters is in uppercase.

Total Grade

Write a function called total_grade(filename, last_name, first_name). This function takes three parameters:

  • filename: the name of a file
  • last_name: the last name of a student
  • first_name: the first name of a student

This function reads the file given by filename, finds all of the records for the student with the given last_name and first_name, and returns the total points earned by that student across all assignments. The format of the file is:



What we want you to get from this lab:

  • You can use the new string functions we have covered

  • You can parse the lines in a file, one line at a time, using split()

  • You can convert between string and integer types as needed

  • You can use split() and join() to parse strings and create new strings

  • You can figure out what went wrong when something unexpected happens

  • Hopefully you had fun!


Turn in a zip file that has your code.

Emoji ReplaceYour solution works1
Emoji Word ReplaceYour solution works1
Total TradesYour solution works2
Find Percent SellerYour solution works2
Uppercase WordsYour solution works2
Uppercase Many WordsYour solution works2