alias magic="python3 -c 'import sys; print(sys.argv[1:])'"

echo start with "['foo', 'bar']"
magic foo bar

echo
echo single-quote "[\"'foo bar'\"]"
magic 'foo bar'

echo
echo double-quote "['\"foo bar\"']"
magic "foo bar"

echo
echo FOOBAR="foo bar"
FOOBAR="foo bar"

echo
echo expand it '['"'"'${FOOBAR}'"'"']'
magic ${FOOBAR}
echo "['foo', 'bar']"
echo POSIX shells will match '^'

echo
echo single-quote the expansion '["'"'"'${FOOBAR}'"'"'"]'
magic '${FOOBAR}'
echo '['"'"'${FOOBAR}'"'"']'
echo POSIX shells will match '^'

echo
echo double-quote the expansion '['"'"'"${FOOBAR}"'"'"']'
magic "${FOOBAR}"
echo '['"'"foo bar"'"']'
echo POSIX shells will match '^'

echo
echo expansion in the middle of abcd '['"'"'ab${FOOBAR}cd'"'"']'
magic ab${FOOBAR}cd
echo '['"'"abfoo"'", "'"barcd"'"']'
echo POSIX shells will match '^'

echo
echo double-quote the expansion in the middle of abcd '['"'"'ab"${FOOBAR}"cd'"'"']'
magic ab"${FOOBAR}"cd
echo '['"'"abfoo barcd"'"']'
echo POSIX shells will match '^'

echo
echo FOOSPACE="foo "
FOOSPACE="foo "

echo
echo double-quote the expansion of FOOSPACE '['"'"'"${FOOSPACE}"'"'"']'
magic "${FOOSPACE}"
echo '['"'"foo "'"']'
echo POSIX shells will match '^' '(note the space)'

echo
echo expansion of FOOSPACE '['"'"'${FOOSPACE}'"'"']'
magic ${FOOSPACE}
echo '['"'"foo"'"']'
echo POSIX shells will match '^' '(note the absence of space)'

echo
echo expansion of 's1=" " s2="" s3=""' '['"'"'${s1}"${s2}"${s3}'"'"']'
export s1=" "
export s2=""
export s3=""
magic ${s1}"${s2}"${s3}
echo '['"''"']'
echo POSIX shells will match '^' '(note the absence of space)'

echo
echo expansion of 's1="" s2=" " s3=""' '['"'"'${s1}"${s2}"${s3}'"'"']'
export s1=""
export s2=" "
export s3=""
magic ${s1}"${s2}"${s3}
echo '['"' '"']'
echo POSIX shells will match '^' '(note the presence of space)'

echo
echo expansion of 's1="" s2="" s3=" "' '['"'"'${s1}"${s2}"${s3}'"'"']'
export s1=""
export s2=""
export s3=" "
magic ${s1}"${s2}"${s3}
echo '['"''"']'
echo POSIX shells will match '^' '(note the absence of space)'

echo
echo expansion of 's1="" s2=" FOO" s3=""' '['"'"'${s1}"${s2}"${s3}'"'"']'
export s1=""
export s2=" FOO"
export s3=""
magic ${s1}"${s2}"${s3}
echo '['"' FOO'"']'
echo POSIX shells will match '^' '(note the presence of space)'