They are all similar, lamdba functions are often passed as a parameter to these functions in Python.
Reduce:
>>> from functools import reduce
>>> reduce((lambda x, y: x + y), [1, 2, 3, 4])
10
Filter:
>>> list(filter((lambda x: x < 0), range(-10,5)))
[-10, -9, -8, -7, - 6, -5, -4, -3, -2, -1]
Map:
>>> list(map((lambda x: x **2), [1,2,3,4]))
[1,4,9,16]
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