how to find substring from string in python code example

Example 1: python find all elements of substring in string

def find_all(a_str, sub):
    start = 0
    while True:
        start = a_str.find(sub, start)
        if start == -1: return
        yield start
        start += len(sub) # use start += 1 to find overlapping matches

list(find_all('spam spam spam spam', 'spam')) # [0, 5, 10, 15]

Example 2: python str contains word

fullstring = "StackAbuse"
substring = "tack"

if substring in fullstring:
    print "Found!"
else:
    print "Not found!"