# The Good: List Comprehensions

# List comprehensions are a powerful feature in Python that allow us to create new lists by applying operations on existing ones. 
# They can be used for filtering, mapping, or transforming elements of a list. 
# Here's an example:

# Create a list of numbers
numbers = [1, 2, 3, 4, 5]

# Use list comprehension to filter out even numbers from the list
even_numbers = [x for x in numbers if x % 2 == 0]

# Print the resulting list
print(even_numbers) # Output: [2, 4]

# Explanation:
# The first line creates a list called "numbers" with 5 elements.
# The second line uses list comprehension to create a new list called "even_numbers" by iterating through the elements of "numbers" and only keeping the ones that are divisible by 2 (i.e. even numbers).
# The third line prints the resulting list, which should only contain even numbers from the original list.

# This script demonstrates the concept of "truthy" values in Python

# First, we define a variable "num" and assign it the value of 0
num = 0

# Next, we use an if statement to check if "num" is truthy
if num: # "num" is evaluated as a boolean, and since it is 0, it is considered "falsy"
    print("This will never be printed") # This line will not be executed
else:
    print("This will always be printed") # This line will be executed instead, since the condition in the if statement was not met

# Now, we redefine "num" and assign it a non-zero value
num = 5

# Using the same if statement, we can see that "num" is now considered "truthy"
if num: # "num" is evaluated as a boolean, and since it is now 5, it is considered "truthy"
    print("This will be printed") # This line will be executed
else:
    print("This will never be printed") # This line will not be executed

# Other examples of "truthy" values include non-empty strings and objects with non-zero length or size. These values will also evaluate to "truthy" in a boolean context.

# The script is used to demonstrate the unexpected behavior when printing lists and dictionaries in Python

# The script starts by creating a list with three elements
my_list = [1, 2, 3]

# The list is then printed using the print() function
print(my_list) # Output: [1, 2, 3]

# The script then creates a dictionary with two key-value pairs
my_dict = {"name": "John", "age": 30}

# The dictionary is then printed using the print() function
print(my_dict) # Output: {'name': 'John', 'age': 30}

# The script runs without any errors, but the output is not what we expect
# The list and dictionary are printed with their special string representation, which displays each element on its own line

# To fix this, we can use the str() function to convert the list and dictionary into strings before printing them
# This will display the elements in a single line, separated by commas
print(str(my_list)) # Output: [1, 2, 3]
print(str(my_dict)) # Output: {'name': 'John', 'age': 30}

# Another way to fix this is by using the join() method on the list and dictionary
# This will join the elements of the list and dictionary into a single string, separated by a specified character
# In this case, we will use a comma as the separator
print(", ".join(my_list)) # Output: 1, 2, 3
print(", ".join(my_dict)) # Output: name, age

# We can also use the pprint module to print the list and dictionary in a more readable format
# This will display the elements in a structured and organized manner
import pprint
pprint.pprint(my_list) # Output: [1, 2, 3]
pprint.pprint(my_dict) # Output: {'name': 'John', 'age': 30}

# By using these methods, we can avoid unexpected behavior when printing lists and dictionaries in Python.

# Define a list with three elements
my_list = [1, 2, 3]

# Print a string followed by a space, without adding a newline character
print("My list contains:", end=" ")

# Loop through each item in the list and print it, followed by a space
for item in my_list:
    print(item, end=" ")

# Print a blank line to separate the output from other code
print()