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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 safe_url(self, url, errors='strict'):
 """URL encode value for safe HTTP request. Args: url (string):
 The string to URL Encode. Returns: (string):
 The urlencoded string. """

        if url is not None:
            url = quote(self.s(url, errors=errors), safe='~')
        return url