not_mandatory

# We need to implement "env with no options or arguments", the output here is optional
env hello world 

# We need to imlement only "cd with only a relative or absolute path"
cd 
cd ~

# Empty export isn't set on `env` but is set on `export`
export hello
env | grep hello
export | grep hello

# This shouldn't break
unset HOME
cd ~

# Local variables are options
aa==vv
echo $aa

# Open pipe waits for input
ls |

# Undefined
<<<
<<<<
> '
echo hi |    |  < >>
echo hi |  < >>   |  |