correspondingFunctionDatabase = [
    [
        ["Java", "System.out.println"], ["JavaScript", "console.log"], ["Python", "print"],
    ],
    [
        ["Java", "s1.replaceAll(str1, str2);"], ["JavaScript", "str.replace(str1, str2)"], ["Python", "str.replace(str1, str2)"], ["Haxe", "replace(str, str1, str2)"]
    ],
    [
        ["JavaScript", "str.split(separator)"], ["Java", "str.split(separator)"], ["Python", "re.split(separator, string)"]
    ],
    [
        ["JavaScript", "eval(statement)"], ["Python", "eval(statement)"] 
    ]
]
 
equivalenceclasses = {n: dict(map(tuple,klass)) for n,klass in enumerate(correspondingFunctionDatabase)}
bypair = {tuple(pair):n for n,klass in enumerate(correspondingFunctionDatabase) for pair in klass}
 
#note pep8 style name
def get_corresponding_function(targetlang, pair):
    # you could catch exceptions here
    return equivalenceclasses.get(bypair.get(tuple(pair))).get(targetlang)
 
print get_corresponding_function("Python", ["Java", "System.out.println"])

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