'Unpack a collection of identities into a list of tuples comprised of
public key blobs and comments.'

def _cbRequestIdentities(self, data):

    if (ord(data[0:1]) != AGENT_IDENTITIES_ANSWER):
        raise ConchError(('unexpected    response:    %i' % ord(data[0:1])))
    numKeys = struct.unpack('!L', data[1:5])[0]
    result = []
    data = data[5:]
    for i in range(numKeys):
        (blob, data) = getNS(data)
        (comment, data) = getNS(data)
        result.append((blob, comment))
    return result
