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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 corrections(self, word, prefix=1, distance=2):
 """Get corrections for word, if word is an invalid word. :prefix: is the number of characters the prefix of the word must have in common with the suggested corrections. :distance: is the character distance the corrections may have between the input word. This limits the number of available corrections but decreases the correction search space. The return value of this function is a Result tuple, with the :valid: member indicating whether the input word is a valid one and :suggestions: member containing a list of suggestions. """

        if word not in self._words:
            return Dictionary.Result(False,
                                     self._corrector.suggest(word,
                                                             prefix=prefix,
                                                             maxdist=distance))
        else:
            return Dictionary.Result(True, list())