Python Flashcards

Question

.

Answer 1

Dot self.x = 10

Answer 2

Equal 4 == 5 == False

Answer 3

Multiplication 2 * 4 == 8

Answer 4

Division 2 / 4 == 0.5

Answer 5

Less than 4 < 4 == False

Answer 6

Greater than 4 > 4 == False

Answer 7

Delete from dictionary. del X[Y]

Answer 8

If an exception happens, do this. except ValueError as e: print(e)

Answer 9

Part of for-loops. Also a test of X in Y. for X in Y: pass also 1 in [1] == True

Answer 10

Logical or. True or False == True

Answer 11

class Person(object)

Answer 12

Part of the with-as statement. with X as Y: pass

Answer 13

Exit the function with a return value. def X(): return Y

Answer 14

Print this string. print('this string')

Answer 15

Create a short anonymous function. s = lambda y: y ** y; s(3)

Answer 16

yield Pause here and return to caller. def X(): yield Y; X().next()

Answer 17

Define a function. def X(): pass

Answer 18

If condition. if: X; elif: Y; else: J

Answer 19

Run a string as Python. exec 'print("hello")'

Answer 20

Import a module into this one to use. import os

Answer 21

Declare that you want a global variable. global X

Answer 22

Else condition. if: X; elif: Y; else: J

Answer 23

This block is empty. def empty(): pass

Answer 24

Importing specific parts of a module. from x import Y

Answer 25

Assert (ensure) that something is true. assert False, "Error!"

Answer 26

Try this block, and if exception, go to except. try: pass

Answer 27

Else if condition. if: X; elif: Y; else: J

Answer 28

Define a class. class Person(object)

Answer 29

Like == to test equality. 1 is 1 == True

Answer 30

Logical and. True and False == False

Answer 31

Loop over a collection of things. for X in Y: pass

Answer 32

Exceptions or not, finally do this no matter what. finally: pass

Answer 33

While loop. while X: pass

Answer 34

Stop this loop right now. while True: break

Answer 35

Raise an exception when things go wrong. raise ValueError("No")

Answer 36

Logical not. not True == False

Answer 37

False boolean value. False and True == False

Answer 38

True boolean value. True or False == True

Answer 39

Stores bytes, maybe of text, PNG, file, etc. x = b"hello"

Answer 40

Stores a list of things. j = [1,2,3,4]

Answer 41

Stores textual information. x = "hello"

Answer 42

Stores a key=value mapping of things. e = {'x': 1, 'y': 2}

Answer 43

Stores decimals. i = 10.389

Answer 44

Represents ”nothing” or ”no value”. x = None

Answer 45

Stores integers. i = 100

Answer 46

How you define a function inside a class.

Answer 47

A phrase to say that something is composed of other things or has a trait, as in ”a salmon has-a mouth.”

Answer 48

A property classes have that are from composition and are usually variables.

Answer 49

What you get when you tell Python to create a class

Answer 50

Two meanings: the most basic type of thing, and any instance of some thing

Answer 51

The concept that one class can inherit traits from another class, much like you and your parents

Answer 52

Tell Python to make a new type of thing.

Answer 53

Inside the functions in a class, self is a variable for the instance/object being accessed

Answer 54

The concept that a class can be composed of other classes as parts, much like how a car has wheels.

Answer 55

A phrase to say that something inherits from another, as in a ”salmon” is-a ”fish.”

Answer 56

The library

Answer 57

In front of

Answer 58

It is stormy

Answer 59

It is windy

Answer 60

Go straight

Answer 61

Directions

Answer 62

The turtle

Answer 63

The post office

Answer 64

The school

Answer 65

Shopping mall

Answer 66

What is the weather like today?

Answer 67

The supermarket

Answer 68

The thunder

Answer 69

Bus station

Answer 70

Embarrassed

Answer 71

To the right of

Answer 72

Autumn/Fall

Answer 73

The weather is bad

Answer 74

The elephant

Answer 75

How is the weather today?

Answer 76

Uncomfortable

Answer 77

The building

Answer 78

The weather

Answer 79

The clouds

Answer 80

Where is…?

Answer 81

It is sunny

Answer 82

The church

Answer 83

The cinema

Answer 84

The office

Answer 85

Train station

Answer 86

It is cold

Answer 87

The animals

Answer 88

The corner

Answer 89

The restaurant

Answer 90

Where are you going?

Answer 91

To go shopping

Answer 92

The fingers

Answer 93

The shoulder

Answer 94

To the left of

Answer 95

It is snowing

Answer 96

Frustrated

Answer 97

The weather is nice

Answer 98

It is rainy

Answer 99

Comfortable

Answer 100

The hair (on head)

Answer 101

The lightning

Answer 102

The stomach

Answer 103

Double-quote

Answer 104

Single-quote

Answer 105

Vertical tab

Answer 106

”class X has-a function named M that takes self and J parameters.”

Answer 107

”Set foo to an instance of class X.”

Answer 108

”From foo, get the M function, and call it with parameters self, J.”

Answer 109

”Make a class named X that is-a Y.”

Answer 110

”From foo, get the K attribute, and set it to Q.”

Answer 111

”class X has-a __init__ that takes self and J parameters.”

Answer 112

A container data type that stores a sequence of elements. Unlike strings, lists are mutable: modification possible. l = [ 1 , 2 , 2 ] print(len(l)) # 3

Answer 113

You can access the (key, value) pairs of a dictionary with the items() method. for k, v in calories.items(): print(k) if v > 500 else None # 'chocolate'

Answer 114

Add elements to a list with (i) append, (ii) insert, or (iii) list concatenation. The append operation is very fast. [ 1 , 2 , 2 ].append( 4 ) # [1, 2, 2, 4] [ 1 , 2 , 4 ].insert( 2 , 2 ) # [1, 2, 2, 4] [ 1 , 2 , 2 ] + [ 4 ] # [1, 2, 2, 4]

Answer 115

A set is an unordered collection of unique elements (“at-most-once”). basket = { 'apple' , 'eggs' , 'banana' , 'orange' } same = set([ 'apple' , 'eggs' , 'banana' , 'orange'] )

Answer 116

This reverses the order of list elements. [ 1 , 2 , 3 ].reverse() # [3, 2, 1]

Answer 117

Sorts a list. The computational complexity of sorting is linear in the no. list elements. [ 2 , 4 , 2 ].sort() # [2, 2, 4]

Answer 118

Python lists can be used intuitively as stacks via the two list operations append() and pop() stack = [3] stack.append( 42 ) # [3, 42] stack.pop() # 42 (stack: [3]) stack.pop() # 3 (stack: [] )

Answer 119

Read and write elements by specifying the key within the brackets. Use the keys() and values() functions to access all keys and values of the dictionary. print(calories[ 'apple' ] < calories[ 'choco' ]) # True calories[ 'cappu' ] = 74 print(calories[ 'banana' ] < calories[ 'cappu' ]) # False print( 'apple' in calories.keys()) # True print( 52 in calories.values()) # True

Answer 120

Check with the ‘in’ keyword whether the set, list, or dictionary contains an element. Set containment is faster than list containment. basket = { 'apple' , 'eggs' , 'banana' , 'orange' } print( 'eggs' in basket) # True print( 'mushroom' in basket) # False

Answer 121

Finds the first occurence of an element in the list & returns its index. Can be slow as the whole list is traversed [ 2 , 2 , 4 ].index( 2 ) # index of element 4 is "0" [ 2 , 2 , 4 ].index( 2 , 1 ) # index of element 2 after pos 1 is "1"

Answer 122

Removing an element can be slower. [ 1 , 2 , 2 , 4 ].remove( 1 ) # [2, 2, 4]

Answer 123

The dictionary is a useful data structure for storing (key, value) pairs. calories = { 'apple' : 52 , 'banana' : 89 , 'choco' : 546 }

Python Flashcards

(255 cards)