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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 antenna1(self, context):
 """ antenna1 data source """

        lrow, urow = MS.uvw_row_extents(context)
        antenna1 = self._manager.ordered_uvw_table.getcol(
            MS.ANTENNA1, startrow=lrow, nrow=urow-lrow)

        return antenna1.reshape(context.shape).astype(context.dtype)