Dan’s 🐍 Python Tricks 💌

# How to merge two dictionaries
# in Python 3.5+:

>>> x = {'a': 1, 'b': 2}
>>> y = {'b': 3, 'c': 4}
>>> z = {**x, **y}
>>> z
{'c': 4, 'a': 1, 'b': 3}

# In Python 2.x you could use this:

>>> z = dict(x, **y)
>>> z
{'a': 1, 'c': 4, 'b': 3}

# Why Python Is Great:
# Function argument unpacking

def myfunc(x, y, z):
    print(x, y, z)

tuple_vec = (1, 0, 1)
dict_vec = {'x': 1, 'y': 0, 'z': 1}

>>> myfunc(*tuple_vec)
1, 0, 1

>>> myfunc(**dict_vec)
1, 0, 1

# The lambda keyword in Python provides a
# shortcut for declaring small and
# anonymous functions:

>>> add = lambda x, y: x + y
>>> add(5, 3)
8

# You could declare the same add()
# function with the def keyword:

>>> def add(x, y):
...     return x + y
>>> add(5, 3)
8

# So what's the big fuss about?
# Lambdas are *function expressions*:
>>> (lambda x, y: x + y)(5, 3)
8

# → Lambda functions are single-expression
# functions that are not necessarily bound
# to a name (they can be anonymous).

# → Lambda functions can't use regular
# Python statements and always include an
# implicit `return` statement.