Your indentation is all over the place – indentation should be in 4 white space blocks, and if and else statements should line up.
A guide to python styling – http://legacy.python.org/dev/peps/pep-0008/#code-lay-out
if os.path.isfile('number.txt'):
print('ESISTE')
f = open('number.txt', 'r')
data = f.read()
f.close()
listOfNumber = data[0:12]
if jid[0:12] in listOfNumber:
print("PRESENTE")
else:
print("DA INSERIRE")
numberAndMessage = jid[0:12] + " " + messageContent
listNumberAndMessage.append(data)
listNumberAndMessage.append(numberAndMessage)
f = open('number.txt', 'w')
for item in listNumberAndMessage:
f.write("%s\n" % item)
f.close()
else: #line with error
print('NON ESISTE')
solved Invalid syntax python else: [closed]