Identify location circles in an image

The goal is to identify location (x,y) of circles in an image. The size and the number of circles are know. Accuracy of the location is of prime importance. The algorithm should be accurate and robust enough to be used on different images. It should be written in python.
Input :
Input to the algorithm should be the images
Output:
- output should the location of the image in csv file
- circles drawn on the image