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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 _get_ssl_context(self, req: 'ClientRequest') -> Optional[SSLContext]: """Logic to get the correct SSL context 0. if req.ssl is false, return None 1. if ssl_context is specified in req, use it 2. if _ssl_context is specified in self, use it 3. otherwise: 1. if verify_ssl is not specified in req, use self.ssl_context (will generate a default context according to self.verify_ssl) 2. if verify_ssl is True in req, generate a default SSL context 3. if verify_ssl is False in req, generate a SSL context that won't verify """

        if req.is_ssl():
            if ssl is None:  # pragma: no cover
                raise RuntimeError('SSL is not supported.')
            sslcontext = req.ssl
            if isinstance(sslcontext, ssl.SSLContext):
                return sslcontext
            if sslcontext is not None:
                # not verified or fingerprinted
                return self._make_ssl_context(False)
            sslcontext = self._ssl
            if isinstance(sslcontext, ssl.SSLContext):
                return sslcontext
            if sslcontext is not None:
                # not verified or fingerprinted
                return self._make_ssl_context(False)
            return self._make_ssl_context(True)
        else:
            return None