Fork for Update source for python3 and my pxssh testing.

test-pxssh.py

##!/usr/bin/env python3
import os
import sys
from pexpect.pxssh import pxssh as PXSSH
import getpass


class Debug_PXSSH(PXSSH):

    def sendline(self, input='') -> int:
        if self.echo_enabled:
            sys.stderr.write('\n[sendline::input={!r}]'.format(input))
        return PXSSH.sendline(self, input)

    def try_read_prompt(self, timeout_multiplier:float):
        prompt = PXSSH.try_read_prompt(self, timeout_multiplier)
        sys.stderr.write('\n[try_read_prompt::prompt={!r}]'.format(prompt))
        sys.stderr.flush()
        return prompt
        
    def sync_original_prompt (self, sync_multiplier=1.0):
        from pexpect import TIMEOUT
        import time
        sys.stderr.write('\n[sync_original_prompt]')
        sys.stderr.flush()
        self.sendline()
        time.sleep(0.1)
        try:
            self.try_read_prompt(sync_multiplier)
        except TIMEOUT:
            pass
        self.sendline()
        x = self.try_read_prompt(sync_multiplier)
        self.sendline()
        a = self.try_read_prompt(sync_multiplier)
        self.sendline()
        b = self.try_read_prompt(sync_multiplier)
        ld = self.levenshtein_distance(a,b)
        len_a = len(a)
        if len_a == 0:
            sys.stderr.write('\n[len_a=0]')
            return False
        val = float(ld)/len_a
        sys.stderr.write('\n[val={}, ld={}, len_a={}]\n'
                         .format(val, ld, len_a))
        sys.stderr.flush()
        if val < 0.4:
            return True
        sys.stderr.write('\n[! distance too far:'
                         '\n{!r}\n{!r}]\n'.format(a, b))
        sys.stderr.flush()
        return False


# setup variables
username = os.environ['USER']
hostname = input('hostname: ')
username = input('username [{}]: '.format(username)).strip() or username
port = int(input('port [22]: ').strip() or '22')
password = getpass.getpass('password: ')

# create and begin session,
session.echo_enabled = False # to suppress echo password.
os.environ["TERM"] = "dumb"
session.login(hostname, username, password, port=port, original_prompt=r"[#$%] ")
session.echo_enabled = True

# note: 
#   os.environ["TERM"] = "dumb" : for colorized remote. without this connect to remote is extreamly slow.
#                               : terminal_type='dumb' not work.
#   original_prompt=r"[#$%] " : if not set I got 'could not synchronize with original prompt'.
#                             : in my case, remote is raspi (bash) so `r"[#$] "` also OK. `r"[#$]"` does not.

session.sendline('uptime')
session.prompt()
sys.stderr.write('\n[session.before={!r}]'.format(session.before))
session.logout()
sys.stderr.write('\n')

I had error 'could not synchronize with original prompt'.
Finally, I have success to connect using normal user with this code.

I tested this with:
local: Mac OS X 10.15.7 with zsh.
remote: raspberry pi Raspbian stretch with bash.