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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:
 async def delete(cls, access_key: str):
 """ Deletes an existing keypair with given ACCESSKEY. """

        q = 'mutation($access_key: String!) {' \
            '  delete_keypair(access_key: $access_key) {' \
            '    ok msg' \
            '  }' \
            '}'
        variables = {
            'access_key': access_key,
        }
        rqst = Request(cls.session, 'POST', '/admin/graphql')
        rqst.set_json({
            'query': q,
            'variables': variables,
        })
        async with rqst.fetch() as resp:
            data = await resp.json()
            return data['delete_keypair']