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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 findPrevStmt(self, block):
 """Returns a tuple that contains the first and last line of the previous statement before line. """

        stmtEnd = self._prevNonCommentBlock(block)
        stmtStart = self.findStmtStart(stmtEnd)
        return Statement(self._qpart, stmtStart, stmtEnd)