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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 __set_URL(self, url):
 """ URL is stored as a str internally and must not contain ASCII chars. Raised exception in case of detected non-ASCII URL characters may be either UnicodeEncodeError or UnicodeDecodeError, depending on the used Python version's str type and the exact value passed as URL input data. """

        if isinstance(url, str):
            url.encode("ascii")  # Check for non-ASCII characters.
            self.url = url
        elif sys.version_info < (3, 0):
            self.url = url.encode("ascii")
        else:
            self.url = url.decode("ascii")