pydoc_grep.sh

#!/bin/sh
#  pydoc_grep <keyword>
#       Grep for the keyword through the pydoc's topics

keyword="${1:?Give me a keyword to look for as a first parameter}"

python -m pydoc 'topics' | awk '/^[A-Z ]+$/ {for (i=1; i<=NF; i++) print $i}' | { 
    unset found
    while read topic; do
        python -m pydoc "$topic" | grep --ignore-case "$keyword" > /dev/null
        [ $? -eq 0 ] && { 
            # print the topic name if it contains the keyword
            echo $topic
            found='yes'
        }
    done
    # correct exit code
    [ "$found" ]
}