Process: FT8 file from WSJT-X

import re
import maidenhead as mh

fl = "C:\\Users\\danielsullivan\\AppData\\Local\\WSJT-X\\ALL.TXT"
fw = "callsign_locations.txt"

lines = None

with open(fl, "r") as rf:
	lines = rf.readlines()
	
with open(fw, "w") as wf:
	wf.write("CALLSIGN")
	wf.write('\t')
	wf.write("DATE")
	wf.write('\t')
	wf.write("FREQ")
	wf.write('\t')
	wf.write("SNR")
	wf.write('\t')
	wf.write("DRIFT_SECONDS")
	wf.write('\t')
	wf.write("GRID")
	wf.write('\t')
	wf.write("LAT")
	wf.write('\t')
	wf.write("LNG")
	wf.write('\n')
	for ln in lines:
		utcd = ln[0:17].strip()

		pts = utcd.split('_')
		
		yr = pts[0][0:2]
		mn = pts[0][2:4]
		dy = pts[0][4:6]
		
		dts = mn + "/" + dy + "/" + yr 
		
		frq = ln[17:24].strip()
		snr = ln[30:38].strip()
		timedrift = ln[37:43].strip()
		msg = ln[47:].strip()
		grd = ""
		lat = None 
		lng = None 
		mparts = msg.split(' ')
		if len(mparts) ==  3:
			chk = mparts[2].strip()
			if len(chk) == 4:
				if chk[0].isalpha() and \
				chk[1].isalpha() and \
				chk[2].isdigit() and \
				chk[3].isdigit():
					print(chk)
					ll = mh.to_location(chk)
					grd = chk
					lat = ll[0]
					lng = ll[1]
					wf.write(mparts[1])
					wf.write('\t')
					wf.write(dts)
					wf.write('\t')
					wf.write(frq)
					wf.write('\t')
					wf.write(snr)
					wf.write('\t')
					wf.write(timedrift)
					wf.write('\t')
					wf.write(grd)
					wf.write('\t')
					wf.write(str(lat))
					wf.write('\t')
					wf.write(str(lng))
					wf.write('\n')