Publish messages from a .csv file the appropriate way

edit

Hello all,

I extracted data from the GPS topic in my recorded bag file into a .csv file. I then modified the lat,lon values to create fake data as desire. Now I want to write a node to publish that modified data to mapviz.

What I expect to do is (with Python API):

1. Parse the .csv file into a junk of NavSatFix data object
2. Loop through that object to publish each messages (similar to each row in the .csv at first)

But I haven't found any tutorial with similar idea. Most of them performs something like

def talker():   
print('in talker')
pub = rospy.Publisher('GPS', NavSatFix, queue_size=10)
rospy.init_node('GPStalker', anonymous=True)
while not rospy.is_shutdown():
    #Assuming that parse will return these values
    time.sleep(1)
    # build navsat message
    fake_gps = NavSatFix()
    fake_gps.header.frame_id = ''
    fake_gps.header.stamp = rospy.Time.now()
    fake_gps.status.status = 1
    fake_gps.status.service = 2
    fake_gps.latitude = 3
    fake_gps.longitude = 4
    fake_gps.altitude = 5

    pub.publish(fake_gps)

My question is, is there a way to implement my idea? Is it efficient? Can you give me some documents or tutorials?