Simple conditions are easily taken care of with if-else statements. In cases that multiple conditions need to be satisfied the statements are extended using an AND operator. This can lead to complex, long, and messy statements as seen in an example below.
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a = 100
b = 10
c = [1, 2, 3, 4, 5]
if a >= 90 and b <= 50 and len(c) == 5:
print("all true")
else:
print("all false")
In Python these statements can be made clearer with the all keyword. Simply put your conditions in a list and call them in the if branch with the keyword all. This way it is immediately clear that all conditions are satisfied. And with proper formatting it is easier to read and modify the different conditions.
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a = 100
b = 10
c = [1, 2, 3, 4, 5]
conditions = [a >= 90,
b <= 50,
len(c) == 5]
if all(conditions):
print("all true")
else:
print("all false")
Where just a single condition out of multiple needs to be satisfied we use an OR operator. Similarly with AND this can lead to difficult to read statements, especially later on when you have to revisit your own code.
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a = 100
b = 10
c = [1, 2, 3, 4, 5]
if a >= 90 or b <= 50 or len(c) < 5:
print("at least one true")
else:
print("all false")
In Python these statements can be made clearer with the any keyword. This follows again the same logic as above. In this case the conditions are chained with the OR operator. Note that with OR only a single condition needs to evaluate as true.
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a = 100
b = 10
c = [1, 2, 3, 4, 5]
conditions = [a >= 90,
b <= 50,
len(c) < 5]
if any(conditions):
print("at least one true")
else:
print("all false")
The lists can be larger than 3 conditions. The larger the number, the more useful the methods all and any will be. However, in the case you have 2 conditions (or 3 really simple ones) using an if statement in combination with and/or will likely be the better option. Readability matters in the end, and this will depend on the number and complexity of the conditions.