Concatenating variables with delimiters, such as comma-separated values, is a common operation in Python when you want to create tags, labels, or lists. This is useful for formatting data for storage or presentation. 

Using Python's .join() Method

Python provides a .join() method, which is an efficient and Pythonic way to concatenate variables with delimiters. This method works on iterable data types, such as lists and strings. 

Example 1: Concatenating List Elements with Commas

# Create a list of items
items = ['apple', 'banana', 'cherry']


# Concatenate the items with commas
comma_separated = ', '.join(items)


# Print the result
print(comma_separated)




Example 2: Concatenating a List of Numbers

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

# Convert numbers to strings and concatenate with hyphens
hyphen_separated = '-'.join(map(str, numbers))

# Print the result
print(hyphen_separated)




Example 3: Concatenating Dictionary Keys

# Create a dictionary
person = {'first_name': 'John', 'last_name': 'Doe', 'age': 30}


# Concatenate dictionary keys with a pipe symbol
key_values = ' | '.join(person.keys())


# Print the result
print(key_values)






Using Custom Functions
You can also create custom functions to concatenate variables with delimiters. This approach gives you more flexibility and control.

Example 4: Concatenating List Elements with Semicolons

# Custom function to concatenate list elements with a semicolon
def custom_join(items, delimiter=';'):
result = ''
for item in items:
result += item + delimiter
# Remove the trailing delimiter
return result[:-1]


# Create a list of items
fruits = ['apple', 'banana', 'cherry']


# Concatenate the items with semicolons using the custom function
semicolon_separated = custom_join(fruits, ';')


# Print the result
print(semicolon_separated)



Conclusion:
Using either the built-in .join() method or a custom function, you can easily concatenate variables with delimiters to create tags, labels, or lists in Python. This is a versatile technique used in data processing, file handling, and text formatting.