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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 rank(keys, axis=semantics.axis_default):
 """where each item is in the pecking order. Parameters keys : indexable object Returns ------- ndarray, [keys.size], int unique integers, ranking the sorting order Notes ----- we should have that index.sorted[index.rank] == keys """

    index = as_index(keys, axis)
    return index.rank