disassemble a windows executable

disass.py

import pefile
import sys
import distorm3

fn = sys.argv[1]

pe = pefile.PE(fn)

try:
    text_section = (
        [ section
          for section in pe.sections
          if section.Name.startswith(b".text")
        ][0]
    )

except IndexError:
    sys.stderr.write("file has no .text section")
    sys.exit(1)

code = text_section.get_data()

disass = distorm3.DecomposeGenerator(0, code, distorm3.Decode32Bits)

for inst in disass:
    sys.stdout.write(
        "%.8x (%d) 0x%-16s %-48s %s\n" % (
            inst.address,
            inst.size,
            inst.instructionBytes.hex(),
            str(inst),
            inst.instructionClass
        )
    )