from datetime import datetime as dt

def flat_dict_to_csv(data):
	keys = set()
	for i in data:
		keys = keys.union(set(i.keys()))
	keys = sorted(keys)
	out = ",".join(keys)
	for i in data:
		out += "\n" + ",".join([str(i.get(j, "")) for j in keys])
	return out

def pretty_ts(timestamp, fmt="%Y-%m-%d %H:%M:%S"):
	d = dt.fromtimestamp(int(timestamp)/1000.0)
	return d.strftime(fmt)