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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 isHereDoc(self, line, column):
 """Check if text at given position is a here document. If language is not known, or text is not parsed yet, ``False`` is returned """

        return self._highlighter is not None and \
               self._highlighter.isHereDoc(self.document().findBlockByNumber(line), column)