Introduction to Python ProgrammingXYZ Homework Edition

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10.1 Dictionary basics

Learning objectives

By the end of this section you should be able to

  • Describe the structure of a dictionary object.
  • Use type to identify the type of a dictionary object.
  • Explain why a dictionary object does not have duplicate key values.

Dictionaries

A dictionary in Python is a container object including key-value pairs. An example of a key-value item is a word in an English dictionary with its corresponding definition.

Dictionary type and properties

The dict type implements a dictionary in Python. Since a dictionary object is used to look up values using keys, a dictionary object cannot hold duplicate key values.

Adapted from Introduction to Python Programming by OpenStax (openstax.org), licensed under CC BY-NC-SA 4.0. Changes were made. License: CC-BY-NC-SA-4.0.

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