Update the documentation to use key_filter instead of f
Update the documentation to use key_filter instead of f

bmess/riak-python-client,basho/riak-python-client,GabrielNicolasAvellaneda/riak-python-client,bmess/riak-python-client,basho/riak-python-client,GabrielNicolasAvellaneda/riak-python-client,basho/riak-python-client