<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def cdx_limit(cdx_iter, limit):
 """ limit cdx to at most `limit`. """

#    for cdx, _ in itertools.izip(cdx_iter, xrange(limit)):
#        yield cdx
    return (cdx for cdx, _ in zip(cdx_iter, range(limit)))