'Retrieve input by session.
Parameters
session : int
Session number to retrieve. The current session is 0, and negative
numbers count back from current session, so -1 is previous session.
start : int
First line to retrieve.
stop : int
End of line range (excluded from output itself). If None, retrieve
to the end of the session.
raw : bool
If True, return untranslated input
output : bool
If True, attempt to include output. This will be \'real\' Python
objects for the current session, or text reprs from previous
sessions if db_log_output was enabled at the time. Where no output
is found, None is used.
Returns
entries
An iterator over the desired lines. Each line is a 3-tuple, either
(session, line, input) if output is False, or
(session, line, (input, output)) if output is True.'

def get_range(self, session=0, start=1, stop=None, raw=True, output=False):

    if (session <= 0):
        session += self.session_number
    if (session == self.session_number):
        return self._get_range_session(start, stop, raw, output)
    return super(HistoryManager, self).get_range(session, start, stop, raw, output)
