MergeByBoolMask.py

import clr
clr.AddReference('ProtoGeometry')
from Autodesk.DesignScript.Geometry import *
#The inputs to this node will be stored as a list in the IN variables.
dataEnteringNode = IN

true_list = IN[0]
false_list = IN[1]
bool_list = IN[2]

result = []
i = 0

for bool in bool_list:
	if bool : result.append(true_list[i])
	else : result.append(false_list[i])
	i = i + 1

#Assign your output to the OUT variable.
OUT = result