The for loop is a generic iterator in python, it can step through the items in any ordered sequence or other iterable object.
Python implements an iterator-based ‘for loop’. It is a type of ‘for loop’ that iterates over a list of items through an explicit or implicit iterator.
The loop is introduced by the keyword ‘for’ which is followed by a random variable name which will contain the values supplied by the object.
The Python for loop begins with a header line that specifies an assignment target, along with the object you want to step through.
for iterating_var in sequence: statements(s)
sum = 0 for x in [1, 2, 3, 4]: sum =sum + x print sum