String operations¶

Which are the values of variables a, b, c, d, l, e, f, g after the execution of these lines of code. Guess it manually and then check your answer using a Python shell.
```
>>> s='abcdef'
>>> a=s[3]
>>> b=s[5]
>>> c=s[0]
>>> l=len(s)
>>> d=s[l-1]
>>> e=s[l-4]
>>> f=s[-1]
>>> g=s[-4]
```
From the initialization of string variable s in the first line, evaluate the following expressions. Guess it manually and then check your answer using a Python shell.
```
>>> s = 'daydreamer'
>>> s[2]
>>> s[-1]
>>> s[:3]
>>> s[-7:]
>>> 'dream' in s
>>> 'dreams' in s
>>> s[-3::-5] + ' ' + s[1::3]
```