7.2 The while statement

  

The while statement is used for repeated execution as long as an expression is true:

while_stmt  ::=  "while" expression ":" suite
    ["else" ":" suite]
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This repeatedly tests the expression and, if it is true, executes the first suite; if the expression is false (which may be the first time it is tested) the suite of the else clause, if present, is executed and the loop terminates.  

A break statement executed in the first suite terminates the loop without executing the else clause's suite. A continue statement executed in the first suite skips the rest of the suite and goes back to testing the expression.   

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