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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 word(self, position):
        '''
        Returns the word instance at the given position in the sentence, None if not found.
        '''
        if 0 <= position < len(self.wordlist):
            return self.wordlist[position]
        else:
            log.warn('position "{}" is not in sentence of length "{}"!'.format(position, len(self.wordlist)))
            raise IndexError()