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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_kernel_id(self):
 """ Get the kernel id of the client. Return a str with the kernel id or None. """

        sessions_url = self.get_session_url()
        sessions_req = requests.get(sessions_url).content.decode()
        sessions = json.loads(sessions_req)

        if os.name == 'nt':
            path = self.path.replace('\\', '/')
        else:
            path = self.path

        for session in sessions:
            notebook_path = session.get('notebook', {}).get('path')
            if notebook_path is not None and notebook_path == path:
                kernel_id = session['kernel']['id']
                return kernel_id