function Utf16Codec(codecOptions, iconv) {
        this.iconv = iconv
      }
Checks if `value` is a native function.

@static
@memberOf _
@since 3.0.0
@category Lang
@param {*} value The value to check.
@returns {boolean} Returns `true` if `value` is a native function,
 else `false`.
@example

_.isNative(Array.prototype.push);
// => true

_.isNative(_);
// => false