To kick things off why do trailing newlines even exist in the first place? Well, it turns out that when you save a text file or copy/paste some code from another source, these newline characters can sneak their way into your string without you even realizing it. And if you’re not careful, they can cause all sorts of problems down the line like unexpected behavior in your program or errors when trying to write data back to a file.

So how do we get rid of them? Well, there are a few different methods depending on what you’re working with and what kind of string manipulation you need to do. Let’s take a look at some examples:

Method 1 Strip()
This method is great for removing whitespace from both the beginning and end of your string. It works by returning a copy of the original string with any leading or trailing whitespace characters (including newlines) removed. Here’s an example:

# Define a string variable with leading and trailing whitespace and a newline character
string = "   Hello, world!\n"

# Use the strip() method to remove the whitespace and newline character from the string
stripped_string = string.strip()

# Print the stripped string, which should now only contain the desired text
print(stripped_string) # Output: 'Hello, world!'

Method 2 Replace() and replace()
This method is a bit more heavy-duty than strip(), as it allows you to search for and replace specific characters or substrings within your string. In this case, we’re using the regular expression ‘\n+’ to match one or more newline characters at the end of our string, then replacing them with an empty string (i.e., removing them). Here’s how it looks:

# Import the regular expression module
import re

# Define a string with extra spaces and a newline character at the end
string = "   Hello, world!\n"

# Use the re.sub() function to replace one or more newline characters at the end of the string with an empty string
stripped_string = re.sub(r'\n+$', '', string)

# Print the stripped string, which should now only contain the original text without any extra spaces or newline characters
print(stripped_string) # Output: 'Hello, world!'

Method 3 Split() and join()
This method is a bit more advanced than the previous two, but it can be really useful for removing trailing newlines in certain situations. The idea here is to split your string into a list of substrings using a delimiter (in this case, we’re using ‘\n’), then joining those substrings back together without any trailing newline characters. Here’s an example:

# The following script is used to remove trailing newlines from a string.

# First, we define a string variable with a trailing newline character.
string = "   Hello, world!\n"

# Next, we split the string into a list of substrings using the newline character as a delimiter.
# The [-1] index is used to access the last substring in the list, which is the one we want to keep.
stripped_list = string.split('\n')[-1]

# The strip() method is used to remove any whitespace characters from the beginning and end of the substring.
stripped_list = stripped_list.strip()

# The join() method is used to join the substrings back together, using the newline character as a delimiter.
# The [:-1] index is used to access all substrings except for the last one, which we already stripped.
# The [-1] index is used to access the last substring, which is the one we want to keep.
stripped_string = "\n".join(stripped_list[:-1]) + stripped_list[-1]

# Finally, we print the stripped string without any trailing newlines.
print(stripped_string) # Output: 'Hello, world!'

And that’s it! With these three methods in your toolbox, you should be able to handle any trailing newline characters that come your way. Of course, there are other ways to remove them as well (like using a for loop or list comprehension), but hopefully this gives you a good starting point.