SGH_zajecia | Python Fiddle

from pprint import pprint

class Task(object):
    callStack = {}

def __init__(self,dependencies=None,fun=None):

if dependencies is not None:
            self.dependencies = dependencies
        else:
            self.dependencies = set()

if fun is not None:
            self.function = fun
        else:
            self.function = None

def set_function(self, fun):
        if fun is None:
            raise TypeError("Argument is None or is not a function")
        self.function = fun

def set_dependencies(self, dependencies):
        if not isinstance(dependencies,[]):
            raise TypeError("Argument is not type of set")
        self.dependencies = dependencies

def add_dependencies(self,dependency):
        if not isinstance(dependency, Task):
            raise TypeError("Argument is not type of Node")
        self.dependencies.append(dependency)

def get_dependencies(self):
        return self.dependencies

def show_dependencies(self):
        pprint(self.dependencies)

def get_value_of_dependencies(self):
        values = []
        for dep in self.dependencies:
            values.append(self.callStack.get(hex(id(dep))))
        return values

def run(self):
        for dep in self.dependencies:
            if self.callStack.get(dep) is None:
                dep.run()

if self.callStack.get(hex(id(self))) is None:
            dependencies_count = len(self.dependencies)
            if dependencies_count>1:
                self.callStack[str(hex(id(self)))] = self.function(self.get_value_of_dependencies())
            elif dependencies_count is 1:
                self.callStack[str(hex(id(self)))] = self.function(self.get_value_of_dependencies()[0])
            else:
                self.callStack[str(hex(id(self)))] = self.function()

return self.callStack[str(hex(id(self)))]

def array_sum(array):
    result = sum([sum(x) for x in zip(*array)])
    return result

def array_multiplication(array,multiplier):
    return map(lambda x: x * multiplier, array)

if __name__=='__main__':
    rangeTask = Task(None, lambda: range(10))
    m2dep = [rangeTask]
    m3dep = [rangeTask]
    multiply2 = Task(m2dep, lambda x: array_multiplication(list(x), 2))
    multiply3 = Task(m2dep, lambda x: array_multiplication(list(x), 3))
    sumDep = [multiply2, multiply3]

sumTask = Task(sumDep, lambda x: array_sum(x))
    print(sumTask.run())

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