Try this:
lst = []
##use append to add items to the list.
lst.append({'A':0,'C':0,'G':0,'T':0})
lst.append({'A':1,'C':1,'G':1,'T':1})
##if u need to add n no of items to the list, use range with append:
for i in range(n):
lst.append({'A':0,'C':0,'G':0,'T':0})
print lst