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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 colstack(self, new, mode='abort'):
 """ Horizontal stacking for tabarrays. Stack tabarray(s) in `new` to the right of `self`. **See also** :func:`tabular.tabarray.tab_colstack`, :func:`tabular.spreadsheet.colstack` """

        if isinstance(new,list):
            return tab_colstack([self] + new,mode)
        else:
            return tab_colstack([self, new], mode)