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Read and write files safely; parse JSON, CSV, and common text formats.

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Files & data easy

How to Write Bytes to a File in Python with 'wb'

Write a bytearray buffer to a binary file using Python's open() in 'wb' mode, then read it back to confirm the data.

bytes file-writing binary-files
Python 
data = bytearray([0x48, 0x65, 0x6c, 0x6c, 0x6f, 0x20, 0x57, 0x6f, 0x72, 0x6c, 0x64])

with open("output.bin", "wb") as f:
    f.write(data)

with open("output.bin", "rb") as f:
    content = f.read()

print(f"Written {len(data)} bytes: {content}")
print(f"As string: {content.decode('ascii')}")
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