environment/lib/python2.7/site-packages/IPython/core/inputsplitter.py
def transform_assign_system(line):
    """Handle the `files = !ls` syntax."""
    m = _assign_system_re.match(line)
    if m is not None:
        cmd = m.group('cmd')
        lhs = m.group('lhs')
        new_line = '%s = get_ipython().getoutput(%r)' % (lhs, cmd)
        return new_line
    return line
def transform_assign_system(line):
    """Handle the `files = !ls` syntax."""
    m = _assign_system_re.match(line)
    if m is not None:
        cmd = m.group('cmd')
        lhs = m.group('lhs')
        new_line = '%s = get_ipython().getoutput(%r)' % (lhs, cmd)
        return new_line
    return line
Handle the `files = !ls` syntax.