Starting Out with Python (4th Edition)
4th Edition
ISBN: 9780134444321
Author: Tony Gaddis
Publisher: PEARSON
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Expert Solution & Answer
Chapter 9, Problem 3TF
Explanation of Solution
Dictionary keys can be tuple:
- • In Python, a dictionary is defined as an unordered collection of data.
- • Each element of the dictionary is a key-value pair.
- • For each key, there is a value mapped to it.
- • The keys in dictionary cannot be modified but the values can be modified.
- • Keys in the dictionary must be immutable objects.
- ○ Immutable Object:
- ■ The object that cannot be modified after its creation is the immutable object.
- ■ Examples of immutable objects are list, array, set, and so on.
- ○ Mutable Object:
- ■ The object that can be modified after its creation is the mutable object.
- ■ Examples of mutable objects are integer, float, string, and so on.
- ○ Immutable Object:
- • Tuples are immutable object that cannot be changed after its creation.
- ○ Tuple is a sequence in which elements cannot be changed after assigned.
- ○ Tuple is similar to list and the only difference is that list can modify the elements whereas tuple cannot modify the elements.
- • Since tuples are immutable object, tuple can be a dictionary key...
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You can create an empty dictionary with
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Exercise: Least Dictionary Value
Description
In this exercise you will find the value in
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Assistant Object inspector
Data structures
dict_from_string(dict_str:str)->dict
This function will be given a single parameter, a string representing a dictionary. Your job is to convert the string into an actual dictionary and return the dictionary. Make sure all key-value pairs in the string exist in the newly created dictionary. The string will contain only numbers or single letters as key values pairs. Make sure all letters are kept as strings and all numbers are converted to integers in the newly created dictionary.
Example:
String Input: '{9: 'V', 'G': 0, 'M': 9, 'u': 3, 2: 'o', 8: 'u', 'q': 9, 'D': 1}'
Expected: {9: 'V', 'G': 0, 'M': 9, 'u': 3, 2: 'o', 8: 'u', 'q': 9, 'D': 1}
String Input: '{10: 'D', 1: 'Z', 5: 'a'}'
Expected: {10: 'D', 1: 'Z', 5: 'a'}
String Input: '{'M': 2, 'V': 0, 3: 'x', 6: 'J', 5: 'J', 7: 'T', 8: 'P', 4: 'q', 1: 'h'}'
Expected: {'M': 2, 'V': 0, 3: 'x', 6: 'J', 5: 'J', 7: 'T', 8: 'P', 4: 'q', 1: 'h'}
String Input: '{3: 'D', 10: 'T', 7: 'm', 'u': 9, 't': 5, 6: 'Z', 'H': 10, 'B':…
Chapter 9 Solutions
Starting Out with Python (4th Edition)
Ch. 9.1 - An element in a dictionary has two parts. What are...Ch. 9.1 - Which part of a dictionary element must be...Ch. 9.1 - Suppose ' start' : 1472 is an element in a...Ch. 9.1 - Suppose a dictionary named employee has been...Ch. 9.1 - What will the following code display? stuff = {1 :...Ch. 9.1 - Prob. 6CPCh. 9.1 - Suppose a dictionary named inventory exists. What...Ch. 9.1 - What will the following code display? stuff = {1 :...Ch. 9.1 - What will the following code display? stuff = {1 :...Ch. 9.1 - What is the difference between the dictionary...
Ch. 9.1 - Prob. 11CPCh. 9.1 - Prob. 12CPCh. 9.1 - What does the values method return?Ch. 9.2 - Prob. 14CPCh. 9.2 - Prob. 15CPCh. 9.2 - Prob. 16CPCh. 9.2 - After the following statement executes, what...Ch. 9.2 - After the following statement executes, what...Ch. 9.2 - After the following statement executes, what...Ch. 9.2 - After the following statement executes, what...Ch. 9.2 - After the following statement executes, what...Ch. 9.2 - Prob. 22CPCh. 9.2 - After the following statement executes, what...Ch. 9.2 - After the following statement executes, what...Ch. 9.2 - Prob. 25CPCh. 9.2 - Prob. 26CPCh. 9.2 - After the following code executes, what elements...Ch. 9.2 - Prob. 28CPCh. 9.2 - After the following code executes, what elements...Ch. 9.2 - After the following code executes, what elements...Ch. 9.2 - After the following code executes, what elements...Ch. 9.2 - Prob. 32CPCh. 9.3 - Prob. 33CPCh. 9.3 - When you open a file for the purpose of saving a...Ch. 9.3 - When you open a file for the purpose of retrieving...Ch. 9.3 - Prob. 36CPCh. 9.3 - Prob. 37CPCh. 9.3 - Prob. 38CPCh. 9 - You can use the __________ operator to determine...Ch. 9 - You use ________ to delete an element from a...Ch. 9 - The ________ function returns the number of...Ch. 9 - You can use_________ to create an empty...Ch. 9 - The _______ method returns a randomly selected...Ch. 9 - The __________ method returns the value associated...Ch. 9 - The __________ dictionary method returns the value...Ch. 9 - The ________ method returns all of a dictionary's...Ch. 9 - The following function returns the number of...Ch. 9 - Prob. 10MCCh. 9 - Prob. 11MCCh. 9 - This set method removes an element, but does not...Ch. 9 - Prob. 13MCCh. 9 - Prob. 14MCCh. 9 - This operator can be used to find the difference...Ch. 9 - Prob. 16MCCh. 9 - Prob. 17MCCh. 9 - The keys in a dictionary must be mutable objects.Ch. 9 - Dictionaries are not sequences.Ch. 9 - Prob. 3TFCh. 9 - Prob. 4TFCh. 9 - The dictionary method popitem does not raise an...Ch. 9 - The following statement creates an empty...Ch. 9 - Prob. 7TFCh. 9 - Prob. 8TFCh. 9 - Prob. 9TFCh. 9 - Prob. 10TFCh. 9 - What will the following code display? dct =...Ch. 9 - What will the following code display? dct =...Ch. 9 - What will the following code display? dct =...Ch. 9 - What will the following code display? stuff =...Ch. 9 - How do you delete an element from a dictionary?Ch. 9 - How do you determine the number of elements that...Ch. 9 - Prob. 7SACh. 9 - What values will the following code display? (Dont...Ch. 9 - After the following statement executes, what...Ch. 9 - After the following statement executes, what...Ch. 9 - After the following statement executes, what...Ch. 9 - After the following statement executes, what...Ch. 9 - After the following statement executes, what...Ch. 9 - What will the following code display? myset =...Ch. 9 - After the following code executes, what elements...Ch. 9 - Prob. 16SACh. 9 - Prob. 17SACh. 9 - Prob. 18SACh. 9 - After the following code executes, what elements...Ch. 9 - Prob. 20SACh. 9 - Write a statement that creates a dictionary...Ch. 9 - Write a statement that creates an empty...Ch. 9 - Assume the variable dct references a dictionary....Ch. 9 - Assume the variable dct references a dictionary....Ch. 9 - Prob. 5AWCh. 9 - Prob. 6AWCh. 9 - Prob. 7AWCh. 9 - Prob. 8AWCh. 9 - Prob. 9AWCh. 9 - Prob. 10AWCh. 9 - Assume the variable dct references a dictionary....Ch. 9 - Write code that retrieves and unpickles the...Ch. 9 - Course information Write a program that creates a...Ch. 9 - Capital Quiz The Capital Quiz Problem Write a...Ch. 9 - File Encryption and Decryption Write a program...Ch. 9 - Unique Words Write a program that opens a...Ch. 9 - Prob. 5PECh. 9 - File Analysis Write a program that reads the...Ch. 9 - World Series Winners In this chapters source code...Ch. 9 - Name and Email Addresses Write a program that...Ch. 9 - Blackjack Simulation Previously in this chapter...Ch. 9 - Word Index Write a program that reads the contents...
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