<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def injectable( name=None, autocall=True, cache=False, cache_scope=_CS_FOREVER, memoize=False):
 """ Decorates functions that will be injected into other functions. Decorator version of `add_injectable`. Name defaults to name of function. The function's argument names and keyword argument values will be matched to registered variables when the function needs to be evaluated by Orca. The argument name "iter_var" may be used to have the current iteration variable injected. """

    def decorator(func):
        if name:
            n = name
        else:
            n = func.__name__
        add_injectable(
            n, func, autocall=autocall, cache=cache, cache_scope=cache_scope,
            memoize=memoize)
        return func
    return decorator