Is there a way of clearing (flushing) the Python Window in ArcMap from Python (that works in 10.2.1)?
Just del data, garbage collection will shortly reclaim the memory.
you seem to have missed del
and if you want to track and otherwise play with the garbage, look at the gc module
import gc
dir(gc)['DEBUG_COLLECTABLE', 'DEBUG_LEAK', 'DEBUG_SAVEALL', 'DEBUG_STATS',
'DEBUG_UNCOLLECTABLE', '__doc__', '__loader__', '__name__', '__package__', '__spec__',
'callbacks', 'collect', 'disable', 'enable', 'garbage', 'get_count', 'get_debug',
'get_objects', 'get_referents', 'get_referrers', 'get_stats', 'get_threshold',
'is_tracked', 'isenabled', 'set_debug', 'set_threshold']