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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 thresholdcoloring(coloring, names):
 """ Threshold a coloring dictionary for a given list of column names. Threshold `coloring` based on `names`, a list of strings in:: coloring.values() **Parameters** **coloring** : dictionary Hierarchical structure on the columns given in the header of the file; an attribute of tabarrays. See :func:`tabular.tab.tabarray.__new__` for more information about coloring. **names** : list of strings List of strings giving column names. **Returns** **newcoloring** : dictionary The thresholded coloring dictionary. """

    for key in coloring.keys():
        if len([k for k in coloring[key] if k in names]) == 0:
            coloring.pop(key)
        else:
            coloring[key] = utils.uniqify([k for k in coloring[key] if k in 
                                           names])
    return coloring