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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 verify(self, tool):
 """ check that the tool exists """

        if os.path.isfile(tool['file']):
            print('Toolbox: program exists = TOK  :: ' + tool['file'])
            return True
        else:
            print('Toolbox: program exists = FAIL :: ' + tool['file'])
            return False