Python

Question 1

Tuples

Answer 1

• immutable objects
• start at 0
• can lookup but can’t change
• more efficient but less flexible

Question 2

Lists

Answer 2

• mutable
• zero based
• can be very flexible and has many functions

Question 3

Strings

Answer 3

“”
Zero index
Immutable

Question 4

Reference Semantics

Answer 4

When assign var to another var it point to address

• 1. Reference of name X is looked up
     
     2. The value at that reference is retrieved
     3. Calculation occurs producing new data element which is assigned to fresh memory location with new reference
     4. The name X is changed to point to this new reference
     5. Old data is garbage collected if no var still refers to it

Question 5

LEGB

Answer 5

1. First search for local definition
2. And if not found there go to Enclosing definition
3. Not found there go to Global definition
4. If not there then go to Built-in definition

Question 6

Local (function)

Answer 6

Names assigned in any way within a function and not declared global in that function

Question 7

Enclosing function locals

Answer 7

Names in the local scope of any and all enclosing functions from inner to outer

Question 8

Global (module)

Answer 8

Names assigned at the top level of a module file or declared global in def within the file

Question 9

Built-in (python)

Answer 9

Names preassigned in the built in names module

Question 10

Class

Answer 10

Is a special data type which defines how to build certain kind of object
-stores some data items that are shared by all the instances of this class

Question 11

Instances

Answer 11

Are objects that are created which follow the definition given inside the class

Question 12

Data attribute

Answer 12

• var owned by a particular instance of a class
• each instance has its own value for it
• these are the most common kind of attribute

Question 13

Class attributes

Answer 13

• owned by the class as a whole
• all instances of the class share the same value for it
• called “static” var

Question 14

First-object

Answer 14

• an argument to a function
• a return value from a function
• assigned to a variable
• a part of container (tuple, list)