#Gorillas vs. Sharks:

You can't simply compare r and python, they're like, well, Gorillas and Sharks.

It's not as simple as: which is better?

And, it's often not the language that's better, but the quality of the code!

#Possible things that could be slowing execution: ###Things not specific to you:

• Beginner's language abuse: as a self-confessed beginner, you may be using the functions or functionality of Python incorrectly.
• Library abuse: Some libraries aren't exactly a walk in the park to use, you may not be using some of the libraries properly.
• Library quality: Assuming library quality is a bit naïve, the actual code behind the library may not be as optimised or good as the other language's implementation.

###Things specific to you:

• Regex: There's many regex being executed, which, is quite a time consuming process, this regex: (?:(?=[.,:;?!) ])|(?<=\( )) managed to register 3000 steps for me!

s = s.lower(), if you're using certain characters in your content, this can have issues.

I'd recommend taking a look over at How do I do a case insensitive string comparison in Python?.

        if n in re.split(r"[ :?.,]", s):
            lc = re.split(r"(^| )" + n + "( |[!\",.:;?})\]])", s)[0]

What is n, re, lc or s? Your variable names are unclear and confusing to read.

#Gorillas vs. Sharks:

You can't simply compare r and python, they're like, well, Gorillas and Sharks.

It's not as simple as: which is better?

And, it's often not the language that's better, but the quality of the code!

#Possible things that could be slowing execution: ###Things not specific to you:

• Beginner's language abuse: as a self-confessed beginner, you may be using the functions or functionality of Python incorrectly.
• Library abuse: Some libraries aren't exactly a walk in the park to use, you may not be using some of the libraries properly.
• Library quality: Assuming library quality is a bit naïve, the actual code behind the library may not be as optimised or good as the other language's implementation.

###Things specific to you:

• Regex: There's many regex being executed, which, is quite a time consuming process, this regex: (?:(?=[.,:;?!) ])|(?<=\( )) managed to register 3000 steps for me!

s = s.lower(), if you're using certain characters in your content, this can have issues.

I'd recommend taking a look over at How do I do a case insensitive string comparison in Python?.

        if n in re.split(r"[ :?.,]", s):
            lc = re.split(r"(^| )" + n + "( |[!\",.:;?})\]])", s)[0]

What is n, re, lc or s? Your variable names are unclear and confusing to read.