# Buggy code
def _make_ssh_client(self, host, **paramiko_kwargs):
    if host not in self.host_clients or self.host_clients[host] is None:
        _user, _port, _password, _pkey = self._get_host_config_values(host)
        self.host_clients[host] = SSHClient(
            host,
            user=_user,
            password=_password,
            port=_port,
            pkey=_pkey,
            forward_ssh_agent=self.forward_ssh_agent,
            num_retries=self.num_retries,
            timeout=self.timeout,
            proxy_host=self.proxy_host,
            proxy_port=self.proxy_port,
            proxy_user=self.proxy_user,
            proxy_password=self.proxy_password,
            proxy_pkey=self.proxy_pkey,
            allow_agent=self.allow_agent,
            agent=self.agent,
            channel_timeout=self.channel_timeout,
            **paramiko_kwargs,
        )


# Traceback (ValueError)
Traceback (most recent call last):
File "./aws-instances", line 172, in <module>
main()
File "./aws-instances", line 73, in main
facts = remote_facts(ips)
File "./aws-instances", line 146, in remote_facts
out_kern = client.run_command('uname -r')
File "/home/user/do-aws-ec2-facts/aws/lib64/python3.6/site-packages/pssh/clients/native/parallel.py", line 223, in run_command
greenlet_timeout=greenlet_timeout)
File "/home/user/do-aws-ec2-facts/aws/lib64/python3.6/site-packages/pssh/clients/base_pssh.py", line 96, in run_command
self.get_output(cmd, output, timeout=greenlet_timeout)
File "/home/user/do-aws-ec2-facts/aws/lib64/python3.6/site-packages/pssh/clients/base_pssh.py", line 141, in get_output
(channel, host, stdout, stderr, stdin) = cmd.get(timeout=timeout)
File "src/gevent/greenlet.py", line 709, in gevent._greenlet.Greenlet.get
File "src/gevent/greenlet.py", line 317, in gevent._greenlet.Greenlet._raise_exception
File "/home/user/do-aws-ec2-facts/aws/lib64/python3.6/site-packages/gevent/_compat.py", line 47, in reraise
raise value.with_traceback(tb)
File "src/gevent/greenlet.py", line 766, in gevent._greenlet.Greenlet.run
File "/home/user/do-aws-ec2-facts/aws/lib64/python3.6/site-packages/pssh/clients/native/parallel.py", line 237, in _run_command
raise ex
File "/home/user/do-aws-ec2-facts/aws/lib64/python3.6/site-packages/pssh/clients/native/parallel.py", line 233, in _run_command
use_pty=use_pty, encoding=encoding, timeout=timeout)
File "/home/user/do-aws-ec2-facts/aws/lib64/python3.6/site-packages/pssh/clients/native/single.py", line 442, in run_command
channel = self.execute(_command, use_pty=use_pty)
File "/home/user/do-aws-ec2-facts/aws/lib64/python3.6/site-packages/pssh/clients/native/single.py", line 324, in execute
channel = self.open_session() if channel is None else channel
File "/home/user/do-aws-ec2-facts/aws/lib64/python3.6/site-packages/pssh/clients/native/single.py", line 297, in open_session
wait_select(self.session)
File "pssh/native/_ssh2.pyx", line 171, in pssh.native._ssh2.wait_select
File "/home/user/do-aws-ec2-facts/aws/lib64/python3.6/site-packages/gevent/select.py", line 145, in select
sel_results = _original_select(rlist, wlist, xlist, 0)
ValueError: filedescriptor out of range in select()

# Fixed code
def _make_ssh_client(self, host_i, host, **paramiko_kwargs):
    if (host_i, host) not in self._host_clients or self._host_clients[
        (host_i, host)
    ] is None:
        _user, _port, _password, _pkey = self._get_host_config_values(host)
        _client = SSHClient(
            host,
            user=_user,
            password=_password,
            port=_port,
            pkey=_pkey,
            forward_ssh_agent=self.forward_ssh_agent,
            num_retries=self.num_retries,
            timeout=self.timeout,
            proxy_host=self.proxy_host,
            proxy_port=self.proxy_port,
            proxy_user=self.proxy_user,
            proxy_password=self.proxy_password,
            proxy_pkey=self.proxy_pkey,
            allow_agent=self.allow_agent,
            agent=self.agent,
            channel_timeout=self.channel_timeout,
            **paramiko_kwargs,
        )
        self.host_clients[host] = _client
        self._host_clients[(host_i, host)] = _client