If multiple requests come in at same time to `/next_url`, can I expect only 1 unique URL to be sent to each request?

app.py

offset = 0
LIMIT = 100
SAVE_AMOUNT = 50
saves = 0
outstanding_urls = {}
pending_results = []

def getMoreURLs():
	global offset
	global LIMIT

	print "getMoreURLS() - OFFSET: %d, LIMIT: %d" % (offset, LIMIT)

	# create SQL query
	cur.execute("SELECT id, url FROM recipes ORDER BY id ASC OFFSET %s LIMIT %s", [str(offset), str(LIMIT)])
	# update offset variable
	offset += LIMIT
	# return query
	return cur.fetchall()


urls = getMoreURLs() # first 100 URLs


@app.route('/api/v1/next_url', methods=['GET'])
def get_next():
	global urls

	if len(urls) > 0:
		url = urls.pop(0)
	else:
		urls = getMoreURLs()
		# Check for any remaining URLs
		if len(urls) == 0:
			return jsonify({'error': 'No more URLs remaining'}) 


	# Create Object
	response_obj = {'id': url[0], 'url': url[1], 'fetched_at': getTime()}

	# Add URL to tracking dict
	outstanding_urls[str(url[0])] = response_obj

	return jsonify(response_obj)