Clustering a dictionary keys using values range

Question

I have a dict (dictionary list of key:value) type of data, in which I want to do clustering of its values according to a range of values.

For example if k = 3 then I want to have 3 groups: the first one with the range of its values starting from 0 to 500, the second group with the value range from 501 to 2000 and the last group with the value range starting from 2001 to 8000.

Any idea how to code that?

Thanks!