(arg, retval=None)
return deco
decorator to smartly _sympify function arguments

       @_sympifyit('other', NotImplemented)
       def add(self, other):
           ...

       In add, other can be thought of as already being a SymPy object.

       If it is not, the code is likely to catch an exception, then other will
       be explicitly _sympified, and the whole code restarted.

       if _sympify(arg) fails, NotImplemented will be returned

       see: __sympifyit
decorator to smartly _sympify function arguments
decorator to smartly _sympify function arguments
def _sympifyit(arg, retval=None):
    """decorator to smartly _sympify function arguments

       @_sympifyit('other', NotImplemented)
       def add(self, other):
           ...

       In add, other can be thought of as already being a SymPy object.

       If it is not, the code is likely to catch an exception, then other will
       be explicitly _sympified, and the whole code restarted.

       if _sympify(arg) fails, NotImplemented will be returned

       see: __sympifyit
    """
    def deco(func):
        return __sympifyit(func, arg, retval)

    return deco
def _sympifyit ( arg , retval = None ) : def deco ( func ) : return __sympifyit ( func , arg , retval ) return deco