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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def confirm_execution(self):
 """Confirm from your if proposed-plan be executed."""

        permit = ''
        while permit.lower() not in ('yes', 'no'):
            permit = input('Execute Proposed Plan? [yes/no] ')
        if permit.lower() == 'yes':
            return True
        else:
            return False