How to use the otree.management.commands.zip.RequirementsError function in otree

# (using __temp prefix makes it show up in the middle, because it's a file)
    archive_name = f'{project_path.name}.otreezip'

    settings_file = project_path / 'settings.py'
    if not settings_file.exists():
        msg = (
            "Cannot find oTree settings. "
            "You must run this command from the folder that contains your "
            "settings.py file."
        )
        logger.error(msg)
        sys.exit(1)

    try:
        check_requirements_files(project_path)
    except RequirementsError as exc:
        logger.error(str(exc))
        sys.exit(1)

    # once Heroku uses py 3.7 by default, we can remove this runtime stuff.
    runtime_txt = project_path / 'runtime.txt'
    runtime_existed = runtime_txt.exists()
    if not runtime_existed:
        # don't use sys.version_info because it might be newer than what
        # heroku supports
        runtime_txt.write_text(f'python-3.7.3')
    try:
        with tarfile.open(archive_name, 'w:gz') as tar:
            # if i omit arcname, it nests the project 2 levels deep.
            # if i say arcname=proj, it puts the whole project in a folder.
            # if i say arcname='', it has 0 levels of nesting.
            tar.add(project_path, arcname='', filter=filter_func)

reqs_base_exists = reqs_base_path.exists()

    if not reqs_path.exists():
        raise RequirementsError("You need a requirements.txt in your project folder")

    with reqs_path.open() as f:
        all_req_lines = get_non_comment_lines(f)

    reqs_base_should_exist = False
    for ln in all_req_lines:
        if 'requirements_base.txt' in ln:
            reqs_base_should_exist = True

    if reqs_base_exists != reqs_base_should_exist:
        if reqs_base_should_exist:
            raise RequirementsError(
                'Your requirements.txt calls requirements_base.txt, '
                'but requirements_base.txt was not found.'
            )
        else:
            raise RequirementsError(
                'Your requirements_base.txt '
                'is being ignored. '
                'Add the following line to requirements.txt:\n'
                '-r requirements_base.txt'
            )

    if reqs_base_exists:
        with reqs_base_path.open() as f:
            all_req_lines.extend(get_non_comment_lines(f))

    psycopg2_found = False

def check_requirements_files(project_path: Path):
    reqs_server_path = project_path / 'requirements_server.txt'
    if reqs_server_path.exists():
        # checking legacy requirements structure is too complicated,
        # skip it.
        return

    reqs_path = project_path / 'requirements.txt'
    reqs_base_path = project_path / 'requirements_base.txt'
    reqs_base_exists = reqs_base_path.exists()

    if not reqs_path.exists():
        raise RequirementsError("You need a requirements.txt in your project folder")

    with reqs_path.open() as f:
        all_req_lines = get_non_comment_lines(f)

    reqs_base_should_exist = False
    for ln in all_req_lines:
        if 'requirements_base.txt' in ln:
            reqs_base_should_exist = True

    if reqs_base_exists != reqs_base_should_exist:
        if reqs_base_should_exist:
            raise RequirementsError(
                'Your requirements.txt calls requirements_base.txt, '
                'but requirements_base.txt was not found.'
            )
        else:

'is being ignored. '
                'Add the following line to requirements.txt:\n'
                '-r requirements_base.txt'
            )

    if reqs_base_exists:
        with reqs_base_path.open() as f:
            all_req_lines.extend(get_non_comment_lines(f))

    psycopg2_found = False
    for ln in all_req_lines:
        if 'psycopg2' in ln:
            psycopg2_found = True

    if not psycopg2_found:
        raise RequirementsError(
            'Your requirements.txt must have a line that says "psycopg2", '
            'which is necessary for Postgres. '
        )

    # check duplicates
    already_seen = set()
    for ln in all_req_lines:

        m = re.match('(^[\w-]+).*?', ln)
        if m:
            package = m.group(1)
            if package in already_seen:
                if reqs_base_exists:
                    raise RequirementsError(
                        f'"{package}" is listed more than once '
                        'in your requirements_base.txt and/or requirements.txt. '

if not psycopg2_found:
        raise RequirementsError(
            'Your requirements.txt must have a line that says "psycopg2", '
            'which is necessary for Postgres. '
        )

    # check duplicates
    already_seen = set()
    for ln in all_req_lines:

        m = re.match('(^[\w-]+).*?', ln)
        if m:
            package = m.group(1)
            if package in already_seen:
                if reqs_base_exists:
                    raise RequirementsError(
                        f'"{package}" is listed more than once '
                        'in your requirements_base.txt and/or requirements.txt. '
                    )
                else:
                    raise RequirementsError(
                        f'"{package}" is listed more than once '
                        'in your requirements.txt. '
                    )
            already_seen.add(package)

# check duplicates
    already_seen = set()
    for ln in all_req_lines:

        m = re.match('(^[\w-]+).*?', ln)
        if m:
            package = m.group(1)
            if package in already_seen:
                if reqs_base_exists:
                    raise RequirementsError(
                        f'"{package}" is listed more than once '
                        'in your requirements_base.txt and/or requirements.txt. '
                    )
                else:
                    raise RequirementsError(
                        f'"{package}" is listed more than once '
                        'in your requirements.txt. '
                    )
            already_seen.add(package)