Pregunta 1
Pregunta
What is the output of the following code snippet: (You can see the picture too)
if 'bar' in {'foo': 1, 'bar': 2, 'baz': 3}:
print(1)
print(2)
if 'a' in 'qux':
print(3)
print(4)
Pregunta 2
Pregunta
The following if/elif/else statement will raise a KeyError exception:
d = {'a': 0, 'b': 1, 'c': 0}
if d['a'] > 0:
print('ok')
elif d['b'] > 0:
print('ok')
elif d['c'] > 0:
print('ok')
elif d['d'] > 0:
print('ok')
else:
print('not ok')
Pregunta 3
Pregunta
Shown below is a diagram of a simple dictionary:
Which of the following is not a valid way to define this dictionary in Python:
Respuesta
-
d = {'foo': 100, 'bar': 200, 'baz': 300}
-
d = {
('foo', 100),
('bar', 200),
('baz', 300)
}
-
d = {}
d['foo'] = 100
d['bar'] = 200
d['baz'] = 300
-
d = dict(foo=100, bar=200, baz=300)
-
d = dict([
('foo', 100),
('bar', 200),
('baz', 300)
])
Pregunta 4
Pregunta
List a is defined as follows:
a = [1, 2, 3, 4, 5]
Select all of the following statements that remove the middle element 3 from a so that it equals [1, 2, 4, 5]:
Respuesta
-
a[2] = []
-
del a[2]
-
a.add(3)
-
a[0:3] = []
-
a[2:2] = []
Pregunta 5
Pregunta
Which of the following would separate a string input_string on the first 2 occurences of the letter “e”?
Respuesta
-
input_string.split('e', 2)
-
'e'.split(input_string, maxsplit=2)
-
'e'.split(input_string, 2)
Pregunta 6
Pregunta
What is the output of the following code snippet:
d = {'foo': 1, 'bar': 2, 'baz': 3}
while d:
print(d.popitem())
print('Done.')
Respuesta
-
Done.
-
foo
bar
baz
-
The snippet doesn’t generate any output.
-
('baz', 3)
('bar', 2)
('foo', 1)
Done.
Pregunta 7
Pregunta
The function sqrt() from the math module computes the square root of a number.
Will the highlighted line of code raise an exception?
x = -100
from math import sqrt
x > 0 and sqrt(x)
Pregunta 8
Pregunta
Which of the following mathematical operators can be used to concatenate strings:
Pregunta 9
Pregunta
Suppose you have the following tuple definition:
t = ('foo', 'bar', 'baz')
Which of the following statements replaces the second element ('bar') with the string 'qux':
Pregunta 10
Pregunta
What is value of this expression:
'a' + 'x' if '123'.isdigit() else 'y' + 'b'