Daniel Arbuckle's Mastering Python
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Flow control statements

Python has several flow control statements that will be familiar to people who know another language in the C family. For example, Python has loops and if, elif, and else branches (shown in the following code example):

selector = 5 
 
if selector < 3: 
    print("less than three") 
elif selector < 6: 
    print("less than six") 
else: 
    print("six or more") 
while selector > 0" 
    print('selector is {}' .format(selector)) 
    selector -=1 
 
for x in ['a', 'b', 'c', 'd']: 
    print(x) 
for x in range(5): 
    print(x) 

Python also has a for loop statement, but it's not like the for loops in C, C++, or Java. Instead of counting through numbers, the for loop iterates through the values. If we actually want to count through numbers with a for loop, that's easily done using a range iterator, as shown in the following screenshot in the output of the preceding code example:

Before we wrap-up this section, there's one last thing I should comment on and that's Python's views on indentation to signify the block structure.