environment/lib/python2.7/site-packages/IPython/utils/dir2.py
def dir2(obj):
    """dir2(obj) -> list of strings

    Extended version of the Python builtin dir(), which does a few extra
    checks, and supports common objects with unusual internals that confuse
    dir(), such as Traits and PyCrust.

    This version is guaranteed to return only a list of true strings, whereas
    dir() returns anything that objects inject into themselves, even if they
    are later not really valid for attribute access (many extension libraries
    have such bugs).
    """

    # Start building the attribute list via dir(), and then complete it
    # with a few extra special-purpose calls.

    words = set(dir(obj))

    if hasattr(obj, '__class__'):
        #words.add('__class__')
        words |= set(get_class_members(obj.__class__))


    # for objects with Enthought's traits, add trait_names() list
    # for PyCrust-style, add _getAttributeNames() magic method list
    for attr in ('trait_names', '_getAttributeNames'):
        if hasattr(obj, attr):
            try:
                func = getattr(obj, attr)
                if callable(func):
                    words |= set(func())
            except:
                # TypeError: obj is class not instance
                pass

    # filter out non-string attributes which may be stuffed by dir() calls
    # and poor coding in third-party modules

    words = [w for w in words if isinstance(w, basestring)]
    return sorted(words)
def dir2(obj):
    """dir2(obj) -> list of strings

    Extended version of the Python builtin dir(), which does a few extra
    checks, and supports common objects with unusual internals that confuse
    dir(), such as Traits and PyCrust.

    This version is guaranteed to return only a list of true strings, whereas
    dir() returns anything that objects inject into themselves, even if they
    are later not really valid for attribute access (many extension libraries
    have such bugs).
    """

    # Start building the attribute list via dir(), and then complete it
    # with a few extra special-purpose calls.

    words = set(dir(obj))

    if hasattr(obj, '__class__'):
        #words.add('__class__')
        words |= set(get_class_members(obj.__class__))


    # for objects with Enthought's traits, add trait_names() list
    # for PyCrust-style, add _getAttributeNames() magic method list
    for attr in ('trait_names', '_getAttributeNames'):
        if hasattr(obj, attr):
            try:
                func = getattr(obj, attr)
                if callable(func):
                    words |= set(func())
            except:
                # TypeError: obj is class not instance
                pass

    # filter out non-string attributes which may be stuffed by dir() calls
    # and poor coding in third-party modules

    words = [w for w in words if isinstance(w, basestring)]
    return sorted(words)
dir2(obj) -> list of strings

    Extended version of the Python builtin dir(), which does a few extra
    checks, and supports common objects with unusual internals that confuse
    dir(), such as Traits and PyCrust.

    This version is guaranteed to return only a list of true strings, whereas
    dir() returns anything that objects inject into themselves, even if they
    are later not really valid for attribute access (many extension libraries
    have such bugs).