字典覆盖
>>> a = {"a":1,"b":2}
>>> b = {"a":10,"b":20}
>>> c = {**a,**b}
>>> c
{'a': 10, 'b': 20}
# If there are common keys between a and b, the values from b will take precedence.Partial Functions
functools.partial is a function in the Python functools module that allows you to create partially-applied versions of functions. Partial application refers to the process of fixing a certain number of arguments of a function and generating a new function that takes the remaining arguments.
Here’s a simple example to illustrate how functools.partial works:
from functools import partial
# Original function
def multiply(a, b):
return a * b
# Create a partial function with the first argument fixed
multiply_by_2 = partial(multiply, 2)
# Now, calling multiply_by_2 is equivalent to multiply(2, b)
result = multiply_by_2(5)
print(result) # Output: 10In this example, partial(multiply, 2) creates a new function multiply_by_2 where the first argument is fixed to 2. When you call multiply_by_2(5), it’s equivalent to calling multiply(2, 5).
functools.partial is often used in scenarios where you need to pass a function with a specific set of parameters, but you want to create a new function with some arguments already filled in. It’s a convenient way to simplify function calls and promote code reuse.
