# -*- coding: utf-8 -*-
"""
Created on Wed Sep 20 08:34:06 2017

@author: Miguel Almeida
"""

def planet_period(planet):
    """Return orbital period
    Use planets.csv
    """
    lines = open('planets.csv').readlines()
    for line in lines:
        parts = line.split(',')
        if parts[0] == planet:
            return float(parts[2])