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Rishi
Rishi

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Learn Python: Booleans & Comparisons

Simply Booleans

Checking for truthy or falsy.

Description Operator
Truthy True
Falsy False
Greater than >
Less than <
Greater or equal to >=
Less or equal to <=
Equals to ==
Assignment =
truthy = True falsy = False print(truthy); print(falsy); LEGAL_AGE = 18 age = int(input("Enter your age:")); is_over_legal_age = age >= LEGAL_AGE; print(f"User is OVER legal age: {is_over_legal_age}") is_under_legal_age = age < LEGAL_AGE; print(f"User is UNDER legal age: {is_under_legal_age}") is_twenty = age == 20; print(f"User is 20 years old: {is_twenty}") is_eighteen = age == 18; print(f"User is 18 years old: {is_eighteen}") 
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bool()

bool() is a function which takes in a parameter and evaluates it to either True or False.

print(f"Integer 0 is evaluated to: {bool(0)}") print(f"An empty character '' is evaluated to: {bool('')}") print(f"Positve number 1 is evaluated to : {bool(1)}") print(f"Negative -1 is evaluated to: {bool(-1)}") print(f"A string 'abc' is evaluated to : {bool('abc')}") 
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and

and gives you the first value if it is False, otherwise, it gives you the second value.

print(f"True and True: { True and True}"); print(f"False and False: { False and False}"); print(f"True and False: { True and False}"); print(f"False and True: { False and True}"); 
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Let's compare some numbers and some strings.

print(f"True and True: { bool(10) and bool(10)}"); print(f"False and False: { bool(0) and bool(10)}"); print(f"True and False: { bool(10) and bool(0)}"); print(f"False and True: { bool(0) and bool(10)}"); print() print(f"10 and 10: { 10 and 10}"); print(f"0 and 0: { 0 and 0}"); print(f"10 and 0: { 10 and 0}"); print(f"0 and 10: { 0 and 10}"); print() print(f"'abc' and 'xyz': { 'abc' and 'xyz'}"); print(f"'' and '': { '' and 'xyz'}"); print(f"'abc' and '': { 'abc' and ''}"); print(f"'' and 'xyz': { '' and 'xyz'}"); 
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or

or gives you the first value if it is True, otherwise it gives you the second value.

print(f"True or True: { True or True}"); print(f"False or False: { False or False}"); print(f"True or False: { True or False}"); print(f"False or True: { False or True}"); 
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Let's compare some numbers and some strings.

print(f"True or True: { bool(10) or bool(10)}"); print(f"False or False: { bool(0) or bool(10)}"); print(f"True or False: { bool(10) or bool(0)}"); print(f"False or True: { bool(0) or bool(10)}"); print() print(f"10 or 10: { 10 or 10}"); print(f"0 or 0: { 0 or 0}"); print(f"10 or 0: { 10 or 0}"); print(f"0 or 10: { 0 or 10}"); print() print(f"'abc' or 'xyz': { 'abc' or 'xyz'}"); print(f"'' or '': { '' or 'xyz'}"); print(f"'abc' or '': { 'abc' or ''}"); print(f"'' or 'xyz': { '' or 'xyz'}"); 
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not

not negates any boolean value.
not True is evaluated to False.
not False is evaluated to True.

print(f"True: { True}" ); print(f"not True: {not True}" ); print() print(f"False: { False}" ); print(f"not False: {not False}" ); print() print(f"35: { 35}" ); print(f"not 35: {not 35}" ); print() print(f"'': { ''}" ); print(f"not '': {not ''}" ); print() print(f"'abc': { 'abc'}" ); print(f"not 'abc': {not 'abc'}" ); 
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