The if statement is a way to make sure that parts
of the code will only be executed under certain
conditions.
if condition: # statements else:
# statements
If the condition following the if is evaluated to True,
the first nested block will be executed. In case of False the second nested block
will be executed, i.e. the one following the else.
if condition1:
# statements
elif condition2:
# statements
else:
# statements
The else-part of the if statement may contain a nested if statement.
In this case we can write “elif” instead of “else if”.