In which file is the private key stored in bytecoin-gui?

[antvolin]

Here are the files I have in my wallet
~ /.bytecoin/ :
data_folder_path.txt
bytecoin-gui.config
bytecoind.lock

~ /.bytecoin/wallet_cache/
xxx.lock
~ /.bytecoin/wallet_cache/xxx/
data.mdb
lock.mdb

~ /.bytecoin/peer_db/
data.mdb
lock.mdb

~ /.bytecoin/logs/
bytecoind-errors_0.log
bytecoind-verbose_0.log
bytecoin-gui.log
walletd-errors_0.log
walletd-verbose_0.log

~ /.bytecoin/blockchain/
data.mdb
lock.mdb

Is it possible to export a private key? In the wallet menu of this option I do not have...

P.S.: my wallet is fully synchronized
And yet, when creating a purse, I specified a file named "bcn", in which the data is of this type:
xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxxx
xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxxx
xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxxx
xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxxx
xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxxx
xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxxx
xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxxx
xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxxx
xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxxx
xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxxx
xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxxx
xxxx xxxx xxxx xxxx xx