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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 obfuscate(cls, idStr):
 """ Mildly obfuscates the specified ID string in an easily reversible fashion. This is not intended for security purposes, but rather to dissuade users from depending on our internal ID structures. """

        return unicode(base64.urlsafe_b64encode(
            idStr.encode('utf-8')).replace(b'=', b''))