This gives control of the child process to the interactive user (the
        human at the keyboard). Keystrokes are sent to the child process, and
        the stdout and stderr output of the child process is printed. This
        simply echos the child stdout and child stderr to the real stdout and
        it echos the real stdin to the child stdin. When the user types the
        escape_character this method will return None. The escape_character
        will not be transmitted.  The default for escape_character is
        entered as ``Ctrl - ]``, the very same as BSD telnet. To prevent
        escaping, escape_character may be set to None.

        If a logfile is specified, then the data sent and received from the
        child process in interact mode is duplicated to the given log.

        You may pass in optional input and output filter functions. These
        functions should take a string and return a string. The output_filter
        will be passed all the output from the child process. The input_filter
        will be passed all the keyboard input from the user. The input_filter
        is run BEFORE the check for the escape_character.

        Note that if you change the window size of the parent the SIGWINCH
        signal will not be passed through to the child. If you want the child
        window size to change when the parent's window size changes then do
        something like the following example::

            import pexpect, struct, fcntl, termios, signal, sys
            def sigwinch_passthrough (sig, data):
                s = struct.pack("HHHH", 0, 0, 0, 0)
                a = struct.unpack('hhhh', fcntl.ioctl(sys.stdout.fileno(),
                    termios.TIOCGWINSZ , s))
                if not p.closed:
                    p.setwinsize(a[0],a[1])

            # Note this 'p' is global and used in sigwinch_passthrough.
            p = pexpect.spawn('/bin/bash')
            signal.signal(signal.SIGWINCH, sigwinch_passthrough)
            p.interact()

def interact(self, escape_character=chr(29),
            input_filter=None, output_filter=None):

        '''This gives control of the child process to the interactive user (the
        human at the keyboard). Keystrokes are sent to the child process, and
        the stdout and stderr output of the child process is printed. This
        simply echos the child stdout and child stderr to the real stdout and
        it echos the real stdin to the child stdin. When the user types the
        escape_character this method will return None. The escape_character
        will not be transmitted.  The default for escape_character is
        entered as ``Ctrl - ]``, the very same as BSD telnet. To prevent
        escaping, escape_character may be set to None.

        If a logfile is specified, then the data sent and received from the
        child process in interact mode is duplicated to the given log.

        You may pass in optional input and output filter functions. These
        functions should take a string and return a string. The output_filter
        will be passed all the output from the child process. The input_filter
        will be passed all the keyboard input from the user. The input_filter
        is run BEFORE the check for the escape_character.

        Note that if you change the window size of the parent the SIGWINCH
        signal will not be passed through to the child. If you want the child
        window size to change when the parent's window size changes then do
        something like the following example::

            import pexpect, struct, fcntl, termios, signal, sys
            def sigwinch_passthrough (sig, data):
                s = struct.pack("HHHH", 0, 0, 0, 0)
                a = struct.unpack('hhhh', fcntl.ioctl(sys.stdout.fileno(),
                    termios.TIOCGWINSZ , s))
                if not p.closed:
                    p.setwinsize(a[0],a[1])

            # Note this 'p' is global and used in sigwinch_passthrough.
            p = pexpect.spawn('/bin/bash')
            signal.signal(signal.SIGWINCH, sigwinch_passthrough)
            p.interact()
        '''

        # Flush the buffer.
        self.write_to_stdout(self.buffer)
        self.stdout.flush()
        self._buffer = self.buffer_type()
        mode = tty.tcgetattr(self.STDIN_FILENO)
        tty.setraw(self.STDIN_FILENO)
        if escape_character is not None and PY3:
            escape_character = escape_character.encode('latin-1')
        try:
            self.__interact_copy(escape_character, input_filter, output_filter)
        finally:
            tty.tcsetattr(self.STDIN_FILENO, tty.TCSAFLUSH, mode)