all Python 3Byte sequencesfunction

bytes.zfill

bytes — padding

Pad on the left with zeros to a given length.

Syntax

b.zfill(...)

A leading plus or minus stays in first position and the zeros are inserted after it — that is exactly what separates zfill from padding with zeros via rjust. Only one such sign byte at the very start is recognised; anything else, including a space or a 0x prefix, counts as ordinary content. A value already at least width bytes long is returned as is, never truncated.

Examples

print(b'42'.zfill(5))   # → b'00042'
print(b'-42'.zfill(5))   # → b'-0042'
print(b'+7'.zfill(6))   # → b'+00007'
print(b'12345'.zfill(3))   # → b'12345'
print(b'7'.zfill(3) + b'.jpg')   # → b'007.jpg'
print(b''.zfill(2))   # → b'00'

See also

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