3.6: Chapter Summary

Highlights from this chapter include:

• A string is a sequence of values that represents Unicode code points.
• An index refers to the position of a value in a sequence (string, list, tuple).
• Positive indexes range from 0 to length–1. Negative indexes range from –1 to –length.
• F-strings are a convenient way to print multiple outputs and format integers and floats.
• Variables refer to objects. Memory diagrams are useful for drawing variables and objects.
• A list object can be used to refer to multiple objects, by index, using the same variable.
• A tuple is similar to a list, but uses parentheses and cannot be changed once created.

Code	Description
ord(c)	Gets an integer representing the Unicode code point of a character.
chr(i)	Converts a Unicode code point (integer) into a One-character string.
'\n'	Escape sequence for the newline character.
'\t'	Escape sequence for the tab character.
f"{number:.02d}"	Creates a string by formatting an integer to be at least two digits.
f"{number:.2f}"	Creates a string by formatting a float to have two decimal places.
id(object)	Gets the identity (memory location) of an object.
type(object)	Gets the type (class name) of an object.
my_list = ["a", "b", "c"]	Creates a list of three strings.
my_tuple = ("a", "b", "c")	Creates a tuple of three strings.
my_list[0]	Gets the first element ("a") of my_tuple.
my_tuple[-1]	Gets the last element ("c") of my_tuple.

Table 3.5 Chapter 3 reference.