Creates an EncryptedData message.
        @param data data to encrypt
        @param cipher cipher.CipherType object represening required
                cipher type
        @param key - byte array used as simmetic key
        @param flags - OR-ed combination of Flags constant

def create(data, cipher, key, flags=0):
        """
        Creates an EncryptedData message.
        @param data data to encrypt
        @param cipher cipher.CipherType object represening required
                cipher type
        @param key - byte array used as simmetic key
        @param flags - OR-ed combination of Flags constant
        """
        bio = Membio(data)
        ptr = libcrypto.CMS_EncryptedData_encrypt(bio.bio, cipher.cipher,
                                                  key, len(key), flags)
        if ptr is None:
            raise CMSError("encrypt data")
        return EncryptedData(ptr)