The syntax
Python provides two repetition statements, while and for. We will
consider while first. The syntax for the while statement is,
while test-expression :
statement
Or, in words, the while statement consists of the
keyword while followed by a test expression, terminated by a colon,
followed by a statement (simple or compound) that will be executed as
long as the text expression is True. Note that the statement(s)
following while must be indented.