var global = require('../internals/global');
var isCallable = require('../internals/is-callable');
var wellKnownSymbol = require('../internals/well-known-symbol');
var $$OBSERVABLE = wellKnownSymbol('observable');
var NativeObservable = global.Observable;
var NativeObservablePrototype = NativeObservable && NativeObservable.prototype;
module.exports = !isCallable(NativeObservable)
|| !isCallable(NativeObservable.from)
|| !isCallable(NativeObservable.of)
|| !isCallable(NativeObservablePrototype.subscribe)
|| !isCallable(NativeObservablePrototype[$$OBSERVABLE]);
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