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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 tab_join(ToMerge, keycols=None, nullvals=None, renamer=None, 
             returnrenaming=False, Names=None):
    '''
    Database-join for tabular arrays.

    Wrapper for :func:`tabular.spreadsheet.join` that deals with the coloring 
    and returns the result as a tabarray.

    Method calls::

            data = tabular.spreadsheet.join

    '''

    [Result,Renaming] = spreadsheet.join(ToMerge, keycols=keycols, 
          nullvals=nullvals, renamer=renamer, returnrenaming=True, Names=Names)

    if isinstance(ToMerge,dict):
        Names = ToMerge.keys()
    else:
        Names = range(len(ToMerge))

    Colorings = dict([(k,ToMerge[k].coloring) if 'coloring' in dir(ToMerge[k])  
                                              else {} for k in Names])
    for k in Names:
        if k in Renaming.keys():
            l = ToMerge[k]
            Colorings[k] = \
                dict([(g, [n if not n in Renaming[k].keys() else Renaming[k][n] 
                       for n in l.coloring[g]]) for g in Colorings[k].keys()])
    Coloring = {}
    for k in Colorings.keys():
        for j in Colorings[k].keys():
            if j in Coloring.keys():
                Coloring[j] = utils.uniqify(Coloring[j] + Colorings[k][j])
            else:
                Coloring[j] = utils.uniqify(Colorings[k][j])

    Result = Result.view(tabarray)
    Result.coloring = Coloring

    if returnrenaming:
        return [Result,Renaming]
    else:
        return Result