In the docstring detection state machine, the first string token is always considered as docstring without considering the context. For example, the first strings in the following example are considered as docstrings:

"abcba".strip("ab")

On the opposite end, if multiple strings are implicitly concatenated then only the first string is considered as docstring:

"first" "second"

Python considers the entire string ("firststring") as the module docstring but the state machine will only say that "first" is docstring while "second" is a normal string.