convert S19 to S19 file (add empty space and create new S19 file)

[fncode246]

how can we fill empty space in S19 file that is less than 4000 bytes and then create new S19 file?
the issue is how to write?

f = bincopy.BinFile("file1.s19")
print(f.info())
f.fill(value=b'\xFF', max_words=4000)   #4000)
print(f.info())
print(type(f))
with open("file2.s19") as s19:
    f.write(f.as_srec())

The error is:
f.write(f.as_srec())
AttributeError: 'BinFile' object has no attribute 'write'

thanks