p = r"D:\__sistem__\Masaustu\FikoYT.Yeni.Cag\flutter\fikatia_merkez\windows\runner\flutter_window.cpp"
with open(p, "rb") as f:
    data = f.read()
if not data.startswith(b'\xef\xbb\xbf'):
    with open(p, "wb") as f:
        f.write(b'\xef\xbb\xbf' + data)
    print("BOM added")
else:
    print("BOM already exists")