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You have to iterate the dictionary for printing the values. The for statement will find all the values of the key and print(diskeys) will output all the values of corresponding keys. Related Article. Create a List. How to convert the dictionary to list in Python? You have a dictionary and you want to convert it into a list. With Python, creating and using a dictionary is much like working with a list, except that you must now define a key and value pair. Here are the special rules for creating a key: The key must be unique. When you enter a duplicate key, the information found in the second entry wins — the.

With Python, creating and using a dictionary is much like working with a list, except that you must now define a key and value pair. Here are the special rules for creating a key:

The key must be unique. When you enter a duplicate key, the information found in the second entry wins — the first entry is simply replaced with the second.

The key must be immutable. This rule means that you can use strings, numbers, or tuples for the key. You can’t, however, use a list for a key.

You have no restrictions on the values you provide. A value can be any Python object, so you can use a dictionary to access an employee record or other complex data. The following steps help you understand how to use dictionaries better.

1Open a Python Shell window.

You see the familiar Python prompt.

2Type Colors = {“Sam”: “Blue”, “Amy”: “Red”, “Sarah”: “Yellow”} and press Enter.

Python creates a dictionary containing three entries with people’s favorite colors. Notice how you create the key and value pair. The key comes first, followed by a colon and then the value. Each entry is separated by a comma.

3Type Colors and press Enter.

You see the key and value pairs. However, notice that the entries are sorted in key order. A dictionary automatically keeps the keys sorted to make access faster, which means that you get fast search times even when working with a large data set. The downside is that creating the dictionary takes longer than using something like a list because the computer is busy sorting the entries.

4Type Colors[“Sarah”] and press Enter.

You see the color associated with Sarah, Yellow. Using a string as a key, rather than using a numeric index, makes the code easier to read and makes it self-documenting to an extent.

By making your code more readable, dictionaries save you considerable time in the long run (which is why they’re so popular). However, the convenience of a dictionary comes at the cost of additional creation time and a higher use of resources, so you have trade-offs to consider.

5Type Colors.keys( ) and press Enter.

The dictionary presents a list of the keys it contains. You can use these keys to automate access to the dictionary.

Generate A Dictionary With Keys With Empty Sets Python Free

6Type the following code (pressing Enter after each line and pressing Enter twice after the last line):

The example code outputs a listing of each of the user names and the user’s favorite color. Using dictionaries can make creating useful output a lot easier. The use of a meaningful key means that the key can easily be part of the output.

7Type Colors[“Sarah”] = “Purple” and press Enter.

Warcraft 3 reign of chaos cd key generator. The dictionary content is updated so that Sarah now likes Purple instead of Yellow.

8Type Colors.update({“Harry”: “Orange”}) and press Enter.

https://solutionsboss.weebly.com/blog/game-mu-offline-cho-pc. A new entry is added to the dictionary.

9Place your cursor at the end of the third line of the code you typed in Step 6 and press Enter.

The editor creates a copy of the code for you. This is a time-saving technique that you can use in the Python Shell when you experiment while using code that takes a while to type. Even though you have to type it the first time, you have no good reason to type it the second time.

10Press Enter twice.

Notice that Harry is added in sorted order. In addition, Sarah’s entry is changed to the color Purple.

11Type del Colors[“Sam”] and press Enter.

Python removes Sam’s entry from the dictionary.

12Repeat Steps 9 and 10.

You verify that Sam’s entry is actually gone.

13Type len(Colors) and press Enter.

The output value of 3 verifies that the dictionary contains only three entries now, rather than 4.

14Type Colors.clear( ) and press Enter. Then, Type len(Colors) and press Enter.

Python reports that Colors has 0 entries, so the dictionary is now empty.

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Each key is separated from its value by a colon (:), the items are separated by commas, and the whole thing is enclosed in curly braces. An empty dictionary without any items is written with just two curly braces, like this: {}.

Keys are unique within a dictionary while values may not be. The values of a dictionary can be of any type, but the keys must be of an immutable data type such as strings, numbers, or tuples.

Accessing Values in Dictionary

To access dictionary elements, you can use the familiar square brackets along with the key to obtain its value. Following is a simple example −

When the above code is executed, it produces the following result −

If we attempt to access a data item with a key, which is not a part of the dictionary, we get an error as follows −

When the above code is executed, it produces the following result −

Updating Dictionary

You can update a dictionary by adding a new entry or a key-value pair, modifying an existing entry, or deleting an existing entry as shown in a simple example given below.

When the above code is executed, it produces the following result −

Delete Dictionary Elements

You can either remove individual dictionary elements or clear the entire contents of a dictionary. You can also delete entire dictionary in a single operation.

To explicitly remove an entire dictionary, just use the del statement. Following is a simple example −

This produces the following result.

An exception is raised because after del dict, the dictionary does not exist anymore.

Note − The del() method is discussed in subsequent section.

Properties of Dictionary Keys

Dictionary values have no restrictions. They can be any arbitrary Python object, either standard objects or user-defined objects. However, same is not true for the keys.

There are two important points to remember about dictionary keys −

(a) More than one entry per key is not allowed. This means no duplicate key is allowed. When duplicate keys are encountered during assignment, the last assignment wins. For example −

When the above code is executed, it produces the following result −

(b) Keys must be immutable. This means you can use strings, numbers or tuples as dictionary keys but something like ['key'] is not allowed. Following is a simple example −

When the above code is executed, it produces the following result −

Built-in Dictionary Functions and Methods

Python includes the following dictionary functions −

Python includes the following dictionary methods −