python - File gets cleared when try to write to it -

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• how append file? 8 answers

i try make possible save progress in python game put following line giving me problems:

dataw = open("data.dat","wb") 

how can stop line clearing file.

you're opening file in write mode:

'w' writing (an existing file same name erased)

emphasis mine

you meant use append mode:

'a' opens file appending