def exec_command(self, command, bufsize=-1, timeout=None, get_pty=False):
    """
    Execute a command on the SSH server.  A new `.Channel` is opened and
    the requested command is executed.  The command's input and output
    streams are returned as Python ``file``-like objects representing
    stdin, stdout, and stderr.
    :param str command: the command to execute
    :param int bufsize:
        interpreted the same way as by the built-in ``file()`` function in
        Python
    :param int timeout:
        set command's channel timeout. See `Channel.settimeout`.settimeout
    :return:
        the stdin, stdout, and stderr of the executing command, as a
        3-tuple
    :raises SSHException: if the server fails to execute the command
    """
running command with paramiko exec_command causes process to sleep before finishing