python 实现pipeline

 题目来源于testdone

Pipeline

As part of a data processing pipeline, complete the implementation of the pipeline method:

• The method should accept a variable number of functions, and it should return a new function that accepts one parameter arg.
• The returned function should call the first function in the pipeline with the parameter arg, and call the second function with the result of the first function.
• The returned function should continue calling each function in the pipeline in order, following the same pattern, and return the value from the last function.

For example, pipeline(lambda x: x * 3, lambda x: x + 1, lambda x: x / 2) then calling the returned function with 3 should return 5.0.

from functools import reduce
def pipeline(*funcs):
    def helper(arg):
        return reduce(lambda a, x: x(a),funcs,arg)
    return helper
            
fun = pipeline(lambda x: x * 3, lambda x: x + 1, lambda x: x / 2)
print(fun(3)) #should print 5.0