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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 get(self, key):
 """ Retrieve pandas object stored in file Parameters key : object Returns ------- obj : same type as object stored in file """

        group = self.get_node(key)
        if group is None:
            raise KeyError('No object named {key} in the file'.format(key=key))
        return self._read_group(group)