You could call it LocateTarget ().
It gives a list of all the indexes of all the targets in theList. In your example, it finds the location of all the 4's in the list.
Did you try to run it yourself to see what it does?
def AlgorithmName (target, thelist):
location = []
for pos in range(0, len(thelist)):
if thelist[pos] == target:
location.append(pos)
return location
theList=[0,1,3,-2,4,5,6,7,9,8,4,3,4,2,3,1,99,99,99]
target = 4
location = AlgorithmName (target,theList)
print(location)
*****
What would this Algorithm be called and what would it do?