Converting Dictionary to List?

Advanced techniques: Master List Comprehension

One line magic: Using List Comprehensions

Cast a transformation spell using list comprehensions, and turn your dictionary into structured lists:

# Key-value tuples - classier than a black tie event
k_v_pairs = [(k, v) for k, v in my_dict.items()]

# Flat list - because even keys and values need a buddy system
flat_list = [elem for pair in my_dict.items() for elem in pair]
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Handling Large Dictionaries: Memory Managed

With large dictionaries, be the memory manager. Use generators to protect your memory estate:

# Generator - serving key-value pairs à la carte
gen = ((k, v) for k, v in my_dict.items())

# Convert generator to list - when you want to be traditional
pairs = list(gen)
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Reduce: It's Not Just for Diets

To merge key-value pairs into a single list, reduce() from the functools module is your friend. This approach is compact like a wristwatch but might be harder for beginners to read:

from functools import reduce
flat_list = reduce(lambda acc, kv: acc + list(kv), my_dict.items(), [])
# Shedding off that tuple fat with list(kv) was necessary, wasn't it? 😉
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Unpacking Dictionaries: Let the Unwrapping Begin

Directly Into Function Calls: Straight to the Point

Unwrap your dictionary keys and values into arguments in your function calls in one swoop. Watch:

def print_items(*args):
    for arg in args:
        print(arg)

# Unpack and print - because all pretty things deserve to be unwrapped!
print_items(*flat_list)
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Selective Unwrapping: Being Choosy

Engage in some healthy discrimination when you only want to filter out certain items.

For example, why not even numbers only club?

even_values = [v for k, v in my_dict.items() if v % 2 == 0]
# Because odd ones just didn't make the cut, sorry! 🙁
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Reversing Dictionaries: Spinning Around

Flip your dictionary keys and values like they're flipping pancakes, using dictionary comprehensions:

reversed_dict = {v: k for k, v in my_dict.items()}
# Who says you can't teach a dictionary new tricks!
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N.B.: This only works if the values are unique and hashable.

Mind the Details: Important Tips & Traps

Python Versions: Evolution Matters

In Python 2 dictionaries, my_dict.items() returns a list, not an iterable view like Python 3. May your cross-version compatibility be always in your favor!

Loop Cleanup: Efficiency is King

When creating lists in a loop, always clean up your loops and clear temporary lists to avoid the unexpected:

all_pairs = []
for sub_dict in list_of_dicts:
    all_pairs.extend(sub_dict.items())
# You didn't think that you'll get away with not emptying the trash, did you?
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Nested Structures: Dive Right In

Dealing with nested structures in dictionaries? It's not as scary as you think. Try extracting nested dictionaries into separate lists or get a clear picture of your expected list format for your victory lap!