Convert given string to SHA1 hash by hexadecimal digest in python

MainMod.py

def sha1Hash(toHash):
        try:
            messageDigest = hashlib.sha1()
            stringM = str(toHash)
            byteM = bytes(stringM, encoding='utf')
            messageDigest.update(byteM)
            return messageDigest.hexdigest()
        except TypeError:
            raise "String to hash was not compatible"