What's the logical value of "string" in Python?

Any non empty string in Python (and most other languages) is true as are all non-zero numbers and non-empty lists, dictionaries, sets and tuples.¹

A nicer way to do what you want is:

name = input("what is your name?")
if name in ("Kamran", "Samaneh"):
    print("That is a nice name")
else:
    print("You have a boring name ;)")

This creates a tuple containing the names that you want and performs a membership test.

^{1 As delnan points out in the comments, this applies to all well written collections. That is, if you implement a custom collection class, make sure that it is false when it's empty.}

http://docs.python.org/library/stdtypes.html#truth-value-testing

"....All other values are considered true — so objects of many types are always true."

In Python an empty string is considered False, True otherwise.

You could use the in operator:

if name in ("Kamran","Samaneh"):
    print("That is a nice name")
else:
    print("You have a boring name ;)")

A non-empty string is True, yes. An empty one is False. This is super-handy.