django1/django/utils/deconstruct.py

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def deconstructible(*args, **kwargs):
"""
Class decorator that allow the decorated class to be serialized
by the migrations subsystem.
Accepts an optional kwarg `path` to specify the import path.
"""
path = kwargs.pop('path', None)
def decorator(klass):
def __new__(cls, *args, **kwargs):
# We capture the arguments to make returning them trivial
obj = super(klass, cls).__new__(cls)
obj._constructor_args = (args, kwargs)
return obj
def deconstruct(obj):
"""
Returns a 3-tuple of class import path, positional arguments,
and keyword arguments.
"""
return (
path or '%s.%s' % (obj.__class__.__module__, obj.__class__.__name__),
obj._constructor_args[0],
obj._constructor_args[1],
)
klass.__new__ = staticmethod(__new__)
klass.deconstruct = deconstruct
return klass
if not args:
return decorator
return decorator(*args, **kwargs)