How to use the bidict._common.DuplicationBehavior function in bidict

.. py:attribute:: IGNORE

        Keep the existing item and ignore the new item when a duplication is
        encountered.

    .. py:attribute:: ON_DUP_VAL

        Used with *on_dup_kv* to specify that it should match whatever the
        duplication behavior of *on_dup_val* is.
    """


DuplicationBehavior.RAISE = RAISE = DuplicationBehavior('RAISE')
DuplicationBehavior.OVERWRITE = OVERWRITE = DuplicationBehavior('OVERWRITE')
DuplicationBehavior.IGNORE = IGNORE = DuplicationBehavior('IGNORE')
DuplicationBehavior.ON_DUP_VAL = ON_DUP_VAL = DuplicationBehavior('ON_DUP_VAL')
_MISS = _Marker('MISSING')


def _proxied(methodname, attrname='_fwd', doc=None):
    """Make a func that calls the indicated method on the indicated attribute."""
    def proxy(self, *args):
        """(__doc__ set dynamically below)"""
        attr = getattr(self, attrname)
        meth = getattr(attr, methodname)
        return meth(*args)
    proxy.__name__ = methodname
    proxy.__doc__ = doc or "Like dict's ``%s``." % methodname
    return proxy

Overwrite an existing item when a duplication is encountered.

    .. py:attribute:: IGNORE

        Keep the existing item and ignore the new item when a duplication is
        encountered.

    .. py:attribute:: ON_DUP_VAL

        Used with *on_dup_kv* to specify that it should match whatever the
        duplication behavior of *on_dup_val* is.
    """


DuplicationBehavior.RAISE = RAISE = DuplicationBehavior('RAISE')
DuplicationBehavior.OVERWRITE = OVERWRITE = DuplicationBehavior('OVERWRITE')
DuplicationBehavior.IGNORE = IGNORE = DuplicationBehavior('IGNORE')
DuplicationBehavior.ON_DUP_VAL = ON_DUP_VAL = DuplicationBehavior('ON_DUP_VAL')
_MISS = _Marker('MISSING')


def _proxied(methodname, attrname='_fwd', doc=None):
    """Make a func that calls the indicated method on the indicated attribute."""
    def proxy(self, *args):
        """(__doc__ set dynamically below)"""
        attr = getattr(self, attrname)
        meth = getattr(attr, methodname)
        return meth(*args)
    proxy.__name__ = methodname
    proxy.__doc__ = doc or "Like dict's ``%s``." % methodname
    return proxy

.. py:attribute:: IGNORE

        Keep the existing item and ignore the new item when a duplication is
        encountered.

    .. py:attribute:: ON_DUP_VAL

        Used with *on_dup_kv* to specify that it should match whatever the
        duplication behavior of *on_dup_val* is.
    """


DuplicationBehavior.RAISE = RAISE = DuplicationBehavior('RAISE')
DuplicationBehavior.OVERWRITE = OVERWRITE = DuplicationBehavior('OVERWRITE')
DuplicationBehavior.IGNORE = IGNORE = DuplicationBehavior('IGNORE')
DuplicationBehavior.ON_DUP_VAL = ON_DUP_VAL = DuplicationBehavior('ON_DUP_VAL')
_MISS = _Marker('MISSING')


def _proxied(methodname, attrname='_fwd', doc=None):
    """Make a func that calls the indicated method on the indicated attribute."""
    def proxy(self, *args):
        """(__doc__ set dynamically below)"""
        attr = getattr(self, attrname)
        meth = getattr(attr, methodname)
        return meth(*args)
    proxy.__name__ = methodname
    proxy.__doc__ = doc or "Like dict's ``%s``." % methodname
    return proxy


class BidictBase(BidirectionalMapping):

Overwrite an existing item when a duplication is encountered.

    .. py:attribute:: IGNORE

        Keep the existing item and ignore the new item when a duplication is
        encountered.

    .. py:attribute:: ON_DUP_VAL

        Used with *on_dup_kv* to specify that it should match whatever the
        duplication behavior of *on_dup_val* is.
    """


DuplicationBehavior.RAISE = RAISE = DuplicationBehavior('RAISE')
DuplicationBehavior.OVERWRITE = OVERWRITE = DuplicationBehavior('OVERWRITE')
DuplicationBehavior.IGNORE = IGNORE = DuplicationBehavior('IGNORE')
DuplicationBehavior.ON_DUP_VAL = ON_DUP_VAL = DuplicationBehavior('ON_DUP_VAL')
_MISS = _Marker('MISSING')


def _proxied(methodname, attrname='_fwd', doc=None):
    """Make a func that calls the indicated method on the indicated attribute."""
    def proxy(self, *args):
        """(__doc__ set dynamically below)"""
        attr = getattr(self, attrname)
        meth = getattr(attr, methodname)
        return meth(*args)
    proxy.__name__ = methodname
    proxy.__doc__ = doc or "Like dict's ``%s``." % methodname
    return proxy