how to create reduce() in python

Question

Currently, I am creating primitive equivalents of function like map, filter, reduce etc.

By primitive equivalents, I mean creating the equivalent of the above stated function, in shortest way possible, via language tools like loops, conditions etc.

To give insight of what i am trying to refer, I have already created primitive equivalents for map and filter.

SYNTAX FOR MAP STATEMENT:-

zip(function(), sequence)

EQUIVALENT FOR MAP:-

[function() for x in sequence]

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SYNTAX FOR FILTER STATEMENT:-

filter(function(), sequence)

EQUIVALENT FOR FILTER:-

[x for x in sequence if (condition)]

The difference between map and filter is that, map takes a generic function, on the other hand filter takes in a function that contains a condition, therefore, the output sequence size may be different then the input size in filter

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Now, I am not able to do the same for reduce. For those who are not familiar with reduce()-

reduce(function(), sequence) function is used to apply a particular function passed in its argument to all of the sequence elements mentioned in the sequence passed along. reduce() has only a single return value, as opposed to a sequence returned by map and filter.

Example demonstrating working of reduce():-

reduce(lambda x, y: x*y, [10, 20, 30])

Output of above statement:-

6000

P.S.:- I don't want lengthy functions/for loops, I want something equivalent to a one liner, like what i did when creating an equivalent for map and filter.