Question 4: Lambda Expressions (20%) Write the following lambda expressions: 1. valid email:takes a string s as argument and returns True if s matches email_regex, and False, otherwise 2. concat_csv strings : takes two strings sl and s2 as arguments and returns a single string consisting of sl and s2 separated by comma. For example, ifthe strings 'ab lc , de-f , xyz' and 'ab1c,de-% ^ f , xyz' are given as arguments, the output must be the string ' abic, de-f , xyz , abic, de-% ^ f , xyz . 3. val_by_ vec : takes an object x and a sequence of objects seq, and returns a sequence (i.e., an iterator) of tuples (x, t[o]), (x, t[1), Hint: Use a generator expression. not self_loop : takes a 2-tuple (a, b) and returns True if a and False, otherwise. 4. !- hb In [24]: # Replace the right-hand side of each lambda with your code valid emaillambda s: True concat_csv strings lambda sl, s2:" val_by_vec - lambda x, t: [ not_self_loop -lambda t: True