Do Python strings end in a terminating NULL?

There is no end-of-string character in Python, at least not one that is exposed and it would be implementation dependent. String objects maintain their own length and it is not something that you need to be concerned with. There are several ways to get the string’s length without using len().

str="man bites dog"
unistr = u'abcd\u3030\u3333'

# count characters in a loop
count = 0
for character in str:
    count += 1
>>> count
13

# works for unicode strings too
count = 0
for character in unistr:
    count += 1
>>> count
6

# use `string.count()`
>>> str.count('') - 1
13
>>> unistr.count(u'') - 1
6

# weird ways work too
>>> max(enumerate(str, 1))[0]
13
>>> max(enumerate(unistr, 1))[0]
6
>>> str.rindex(str[-1]) + 1
13
>>> unistr.rindex(unistr[-1]) + 1
6

# even weirder ways to do it
import re
pattern = re.compile(r'$')
match = pattern.search(str)
>>> match.endpos
13
match = pattern.search(unistr)
>>> match.endpos
6

I suspect that this is just the tip of the iceberg.