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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def binary(self, new_binary):
 """Sets location of the browser binary, either by string or ``FirefoxBinary`` instance. """

        if not isinstance(new_binary, FirefoxBinary):
            new_binary = FirefoxBinary(new_binary)
        self._binary = new_binary