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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 write_var_column(self, column, data, firstrow=0, **keys):
 """ Write data to a variable-length column in this HDU This HDU must be a table HDU. parameters column: scalar string/integer The column in which to write. Can be the name or number (0 offset) column: ndarray Numerical python array to write. This must be an object array. firstrow: integer, optional At which row you should begin writing. Be sure you know what you are doing! For appending see the append() method. Default 0. """


        if not is_object(data):
            raise ValueError("Only object fields can be written to "
                             "variable-length arrays")
        colnum = self._extract_colnum(column)

        self._FITS.write_var_column(self._ext+1, colnum+1, data,
                                    firstrow=firstrow+1)
        self._update_info()