Python

Question 1

How would you define a function in Python?

Answer 1

def functionName(args...):
      return value

Question 2

What is the equivalent of a javascript array in python?

Answer 2

It’s a list.

Question 3

How do you define a list in Python?

Answer 3

listName = []

Question 4

How do you initialize a list with 11 slots in python?

Answer 4

list = [None] * 11

Question 5

Are python lists typed?

Answer 5

No.

Question 6

How do you define a class in python?

Answer 6

class MyCustomHashTable:
    def \_\_init\_\_(self, length):
        self.table = ['None'] * length

def findItemHashPosition(self, item):
    return remainder(item, self.length()) ~~~ ~~~

Question 7

How do you convert a string to integer in python?

Answer 7

(int('1') == 1) == True

Question 8

How do you convert an integer to string in python?

Answer 8

('{}'.format(1) == '1') == True

Question 9

How do you define a calculated property in Python?

Answer 9

You can define calculated properties in python by using the @property decorator. The @property decorator acts as a getter and enables retrieving its result by simply accessing its name like a property. ` MyCustomHashTable(11).tableSize `

class MyCustomHashTable:

def \_\_init\_\_(self, length):
    self.table = ['None'] * length ~~~

    @property
    def tableSize(self):
        return len(self.table)

print(MyCustomHashTable(11).tableSize) // prints 11
~~~

Question 10

How do you define infinity in Python?

Answer 10

print(float("inf") > 9999 // prints True

Question 11

How do you check if a value is a bool in Python?

Answer 11

There are three ways to check type equality in Python.

print(type(True) == bool)
print(isinstance(True, bool))
print(issubclass(True, bool))

A few more things to consider.

isinstance

Use this built-in function to find out if a given object is an instance of a certain class or any of its subclasses. You can even pass a tuple of classes to be checked for the object. The only gotcha you will discover is this: in Python a bool object is an instance of int! Yes, not kidding!

issubclass

This built-in function is similar to isinstance, but to check if a type is an instance of a class or any of its subclasses. Again, the only gotcha is that bool type is subclass of int type.

type

If a single argument (object) is passed to type() built-in, it returns type of the given object. If three arguments (name, bases and dict) are passed, it returns a new type object.

A few more things to consider…

>>> isinstance(True, int)
True
>>> isinstance(True, float)
False
>>> isinstance(3, int)
True
>>> isinstance([1,2,3], list)
True
>>> isinstance("aa", str)
True
>>> isinstance(u"as", unicode)
True
>>> issubclass(bool, int)
True

Question 12

How do you iterate through the characters of a string in Python?

Answer 12

A string in python is iterable and has native support.

for char in "string":
  print char

That prints

s
t
r
i
n
g