Generate 440Hz (note A) wave file on Windows with Python

freq.py

import mmap
import winsound as ws
import struct as st
from math import sin, cos, radians
from random import randint

# in RIFF format (and therefore in WAVE) ALL NUMBERS ARE LITTLE ENDIAN

FILE_SIZE = 44100*10+44 # bytes

FREQ = 440 # Hz
SAMPLE_FREQ = 44100 # Hz

#s = mmap.mmap(-1, FILE_SIZE)
s = open("1.wav", "wb")

s.write(b"RIFF") # 4B
s.write( st.pack("<I", FILE_SIZE-8) ) # file size - 8
s.write(b"WAVE") # 4B

s.write(b"fmt ")
s.write( st.pack("<I", 0x10) ) # chunk data size - always 0x10
s.write( st.pack("<I", 0x00010001) ) # 2B compression code (0x01)
                                    # and 2B channel numbers (0x01)
s.write( st.pack("<I", SAMPLE_FREQ) ) # 4B sample rate in Hz
s.write( st.pack("<I", SAMPLE_FREQ*2) ) # 4B Bytes/sec

# 2B Bytes/sample: 1=8bit mono;$ 2=8bit stereo OR 16bit mono; 4=16bit stereo
# 2B bits/sample
s.write( bytes.fromhex("02 00 10 00") )
#s.write( bytes[02,00,10,00] )
#s.write(b"\x02\x00\x10\x00")

s.write(b"data")
s.write( st.pack("<I", FILE_SIZE-11*4) ) # 4B length of data to follow

#sound samples
for i in range(int((FILE_SIZE-11*4) / 2)):
    x = int( sin( radians( i * FREQ/(SAMPLE_FREQ/360/2) ) ) * 32767 )
    #x = randint(0,65535) # white noise
    s.write( st.pack( "<i", x ) )
    
s.close()

ws.PlaySound("1.wav", ws.SND_FILENAME)
#ws.PlaySound(s,ws.SND_MEMORY)