export | grep "SHLVL"
export | grep "OLDPWD"
export | grep "PWD"
export TEST
export TEST
export TEST=123
export ___TEST=123
export --TEST=123
export ""=""
export ''=''
export "="="="
export '='='='
export TE\\\ST=100
export TE-ST=100
export -TEST=100
export TEST-=100
export _TEST=100
export TEST
export ==========
export 1TEST=
export TEST
export ""=""
export TES=T=""
export TE+S=T=""
export TES\\\\T=123
export TES.T=123
export TES\\\$T=123
export TES\\\\T
export TES.T=123
export TES+T=123
export TES=T=123
export TES}T=123
export TES{T=123
export TES-T=123
export -TEST=123
export _TEST=123
export TES_T=123
export TEST_=123
export TE*ST=123
export TES#T=123
export TES@T=123
export TES!T=123
export TES$?T=123
export =============123
export +++++++=123
export ________=123
export export
export echo
export pwd
export cd
export export
export unset
export sudo
export TES^T=123
export TES!T=123
export TES\~T=123
export TEST+=100