d = {1:'a',2:'b',3:'c',4:'b'}
        _uniqualize(d)

def _uniqualize(d):
    '''
        d = {1:'a',2:'b',3:'c',4:'b'}
        _uniqualize(d)
    '''
    pt = copy.deepcopy(d)
    seqs_for_del =[]
    vset = set({})
    for k in pt:
        vset.add(pt[k])
    tslen = vset.__len__()
    freq = {}
    for k in pt:
        v = pt[k]
        if(v in freq):
            freq[v] = freq[v] + 1
            seqs_for_del.append(k)
        else:
            freq[v] = 0
    npt = {}
    for k in pt:
        if(k in seqs_for_del):
            pass
        else:
            npt[k] = pt[k]
    pt = npt
    return(npt)