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https://docs.python.org/3/library/struct.html

#!/usr/bin/python
 
# Example how to receive UDP Data from X-Plane 10 in Python3. 
 
# License: 
# 1) GPLv3
# 2) Consider it as programmer documentation, so you are free to copy some lines ignoring the License. 
 
# Configure Data-Output types 3, 17 and 20
# and the IP where the python script is running (port 49000) in X-Plane.  
 
UDP_PORT = 49002
 
import socket
import struct 
 
def DecodeDataMessage(message):
  # Message consists of 4 byte type and 8 times a 4byte float value.
  # Write the results in a python dict. 
  values = {}
  typelen = 4
  type = int.from_bytes(message[0:typelen], byteorder='little')
  data = message[typelen:]
  dataFLOATS = struct.unpack("<ffffffff",data)
  if type == 3:
    values["speed"]=dataFLOATS[0]
  elif type == 17:
    values["pitch"]=dataFLOATS[0]
    values["roll"]=dataFLOATS[1]
    values["heading"]=dataFLOATS[2]
    values["heading2"]=dataFLOATS[3]
  elif type == 20:
    values["latitude"]=dataFLOATS[0]
    values["longitude"]=dataFLOATS[1]
    values["altitude MSL"]=dataFLOATS[2]
    values["altitude AGL"]=dataFLOATS[3]
    values["altitude 2"]=dataFLOATS[4]
    values["altitude 3"]=dataFLOATS[5]
  else:
    print("  Type ", type, " not implemented: ",dataFLOATS)
  return values
 
def DecodePacket(data):
  # Packet consists of 5 byte header and multiple messages. 
  valuesout = {}
  headerlen = 5
  header = data[0:headerlen]
  messages = data[headerlen:]
  if(header==b'DATA*'):
    # Divide into 36 byte messages
    messagelen = 36
    for i in range(0,int((len(messages))/messagelen)):
      message = messages[(i*messagelen) : ((i+1)*messagelen)]
      values = DecodeDataMessage(message)
      valuesout.update( values )
  else:
    print("Packet type not implemented. ")
    print("  Header: ", header)
    print("  Data: ", messages)
  return valuesout
 
def main():
 
  # Open a Socket on UDP Port 49000
  UDP_IP = ""
  sock = socket.socket(socket.AF_INET, # Internet
                       socket.SOCK_DGRAM) # UDP
  sock.bind((UDP_IP, UDP_PORT))
 
  while True:
    # Receive a packet
    data, addr = sock.recvfrom(1024) # buffer size is 1024 bytes
 
    # Decode the packet. Result is a python dict (like a map in C) with values from X-Plane.
    # Example:
    # {'latitude': 47.72798156738281, 'longitude': 12.434000015258789, 
    #   'altitude MSL': 1822.67, 'altitude AGL': 0.17, 'speed': 4.11, 
    #   'roll': 1.05, 'pitch': -4.38, 'heading': 275.43, 'heading2': 271.84}
    values = DecodePacket(data)
    print(values)
    print()
 
if __name__ == '__main__':
  main()