Lint fixes: false -> False, missing imports, Index list, not map iter

Change-Id: Iff4123a49c8dbcfc405612c0663d5c7d0f549748
diff --git a/pySim/utils.py b/pySim/utils.py
index c5cf480..f7d099b 100644
--- a/pySim/utils.py
+++ b/pySim/utils.py
@@ -249,7 +249,7 @@
 	"""
 	Calculate Luhn checksum used in e.g. ICCID and IMEI
 	"""
-	num = map(int, str(cc))
+	num = list(map(int, str(cc)))
 	check_digit = 10 - sum(num[-2::-2] + [sum(divmod(d * 2, 10)) for d in num[::-2]]) % 10
 	return 0 if check_digit == 10 else check_digit