2- how python runs programs

Question 1

What really happens when a python program runs?

Answer 1

first the source is complied into bytecode, then this is routed to the virtual machine

Question 2

The compiler creates a new file, what is the extension?

Answer 2

.pyc

Question 3

In python 3.2 and later, the bytecode files are saved in what directory?

Answer 3

__pychache__

Question 4

what does Python check to see if the bytecode files need to be updated?

Answer 4

The last modified timestamps of both the source and the byte code files. It also check the version of Python from the byte code.

Question 5

can Python run a program with only bytecode files ( no source)

Answer 5

yes

Question 6

What is a namespace?

Answer 6

package of variable names

Question 7

what is a module

Answer 7

it’s just a .py file.

Question 8

When a module is imported, what is the last thing that is done?

Answer 8

it’s run.

Question 9

what are names within packages called?

Answer 9

attributes. These are simply variable names for specific objects.

Question 10

what is the difference between import an from

Answer 10

from does one extra thing. From copies a modules attributes, so that they become variables in the recipient.

Question 11

what is the syntax to use from in a file called test1 and a attribute called blaster

Answer 11

from test1 import blaster

Question 12

what function prints an imported module’s names in a list

Answer 12

dir

Question 13

What is the python conceptual hierarchy?

Answer 13

Programs are composed of modules. Modules contain Statements. Statements contain expressions. Expression create and process objects.