human
assert command not found.
assistant
Here is a Python function to assert command not found

import sys

def assert_command_not_found(command):
    """
    Assert command not found
    """
    assert command not in sys.argv, "Command %s not found" % command

# Enter the command
command = "assert"

# Calling the function
print((assert_command_not_found(command)))

#Example Output
# None

#Remember to inspect code for bugs.