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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 insert(self, i, *exprs):
 """Insert content at specified position into expression. :param int i: Position to add content to :param Union[TexExpr,str] exprs: List of contents to add TexExpr('textbf', ['hello']) TexExpr('textbf', ['world', 'hello']) """

        self._assert_supports_contents()
        for j, expr in enumerate(exprs):
            self._contents.insert(i + j, expr)