Underscore _ - Nhiều ý nghĩa khác nhau

>>> 2 + 3
5
>>> _
5
>>> _ * 2
10

# Không quan tâm giá trị
for _ in range(5):
    print("Hello")
 
# Unpacking
x, _, z = (1, 2, 3)  # Bỏ qua giá trị thứ 2

# Dễ đọc
million = 1_000_000
billion = 1_000_000_000
 
# Binary
bits = 0b_1010_1100

# Single underscore
class MyClass:
    def _internal(self):  # "Private" method
        pass
 
# Double underscore
class MyClass:
    def __private(self):  # Name mangling
        pass

class MyClass:
    def __init__(self):  # Constructor
        pass
 
    def __str__(self):   # String representation
        pass

# Common convention
from gettext import gettext as _
 
print(_("Hello, World!"))

for _ in range(n): ...  # Throwaway
x, _, z = values        # Ignore middle
num = 1_000_000         # Readability