# Extended stream operations on io.BytesIO
try:
import uio as io
except ImportError:
import io
a = io.BytesIO()
print(a.seek(8))
a.write(b"123")
print(a.getvalue())
print(a.seek(0, 1))
print(a.seek(-1, 2))
a.write(b"0")
a.flush()