def check_object_creation(req, object_name):
    """
    Check to ensure that everything is alright about an object to be created.

    :param req: HTTP request object
    :param object_name: name of object to be created
    :returns HTTPRequestEntityTooLarge: the object is too large
    :returns HTTPLengthRequired: missing content-length header and not
                                 a chunked request
    :returns HTTPBadRequest: missing or bad content-type header, or
                             bad metadata
    :returns HTTPNotImplemented: unsupported transfer-encoding header value
    """
    try:
        ml = req.message_length()
    except ValueError as e:
        return HTTPBadRequest(request=req, content_type='text/plain',
                              body=str(e))
    except AttributeError as e:
        return HTTPNotImplemented(request=req, content_type='text/plain',
                                  body=str(e))
    if ml is not None and ml > MAX_FILE_SIZE:
        return HTTPRequestEntityTooLarge(body='Your request is too large.',
                                         request=req,
                                         content_type='text/plain')
    if req.content_length is None and \
            req.headers.get('transfer-encoding') not in 'chunked':
        return HTTPLengthRequired(body='Missing Content-Length header.',
                                  request=req,
                                  content_type='text/plain')

    if 'X-Copy-From' in req.headers and req.content_length:
        return HTTPBadRequest(body='Copy requests require a zero byte body',
                              request=req, content_type='text/plain')

    if len(object_name) > MAX_OBJECT_NAME_LENGTH:
        return HTTPBadRequest(body='Object name length of %d longer than %d' %
                              (len(object_name), MAX_OBJECT_NAME_LENGTH),
                              request=req, content_type='text/plain')

    if 'Content-Type' not in req.headers:
        return HTTPBadRequest(request=req, content_type='text/plain',
                              body='No content type')

    try:
        req = check_delete_headers(req)
    except HTTPException as e:
        return HTTPBadRequest(request=req, body=e.body,
                              content_type='text/plain')

    if not check_utf8(req.headers['Content-Type']):
        return HTTPBadRequest(request=req, body='Invalid Content-Type',
                              content_type='text/plain')
    return check_metadata(req, 'object')
dataset/ETHPy150Open openstack/swift/swift/common/constraints.py/check_object_creation/operator `!=` -> `not in`