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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 convert_consonantal_i(self, word) -> str: """Convert i to j when at the start of a word."""

        match = list(self.consonantal_i_matcher.finditer(word))
        if match:
            if word[0].isupper():
                return "J" + word[1:]
            return "j" + word[1:]
        return word