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Find the most likely word alignment between two strings in Python

I have 2 similar strings. How can I find the most likely word alignment between these two strings in Python?
Example of input:
string1 = 'my channel is youtube dot com slash example and then I also do live streaming on twitch.'
string2 = 'my channel is youtube.com/example and then I also do livestreaming on twitch.'
Desired output:
alignment['my'] = 'my'
alignment['channel'] = 'channel'
alignment['is'] = 'is'
alignment['youtube'] = 'youtube.com/example'
alignment['dot'] = 'youtube.com/example'
alignment['com'] = 'youtube.com/example'
alignment['slash'] = 'youtube.com/example'
alignment['example'] = 'youtube.com/example'
alignment['and'] = 'and'
alignment['then'] = 'then'
alignment['I'] = 'I'
alignment['also'] = 'also'
alignment['do'] = 'do'
alignment['live'] = 'livestreaming'
alignment['streaming'] = 'livestreaming'
alignment['on'] = 'on'
alignment['twitch'] = 'twitch'

Alignment is tricky. spaCy can do it (see Aligning tokenization) but AFAIK it assumes that the two underlying strings are identical which is not the case here.
I used Bio.pairwise2 a few years back for a similar problem. I don't quite remember the exact settings, but here's what the default setup would give you:
from Bio import pairwise2
from Bio.pairwise2 import format_alignment
string1 = 'my channel is youtube dot com slash example and then I also do live streaming on twitch.'
string2 = 'my channel is youtube.com/example and then I also do livestreaming on twitch.'
alignments = pairwise2.align.globalxx(string1.split(),
string2.split(),
gap_char=['-']
)
The resulting alignments - pretty close already:
>>> format_alignment(*alignments[0])
my channel is youtube dot com slash example - and then I also do live streaming - on twitch.
| | | | | | | | | |
my channel is - - - - - youtube.com/example and then I also do - - livestreaming on twitch.
Score=10
You can provide your own matching functions, which would make fuzzywuzzy an interesting addition.

Previous answers offer biology-based alignment methods, there are NLP-based alignments methods as well. The most standard would be the Levenshtein edit distance. There are a few variants, and generally this problem is considered closely related to the question of text similarity measures (aka fuzzy matching, etc.). In particular it's possible to mix alignment at the level of word and characters. as well as different measures (e.g. SoftTFIDF, see this answer).

The Needleman-Wunch Algorithm
Biologists sometimes try to align the DNA of two different plants or animals to see how much of their genome they share in common.
MOUSE: A A T C C G C T A G
RAT: A A A C C C T T A G
+ + - + + - - + + +
Above "+" means that pieces of DNA match.
Above "-" means that pieces of DNA mis-match.
You can use the full ASCII character set (128 characters) instead of the letters ATCG that biologists use.
I recommend using the the Needleman Wunsch Algorithm
Needle-Wunsch is not the fastest algorithm in the world.
However, Needle-Wunsch is easy to understand.
In cases were one string of English text is completely missing a word present in the other text, Needleman Wunsch will match the word to special "GAP" character.
+-------+--------+-------+---+------+----+-----+-------+-----+----+-----+-------+------+
| The | reason | that | I | went | to | the | store | was | to | buy | some | food |
+-------+--------+-------+---+------+----+-----+-------+-----+----+-----+-------+------+
| <GAP> | reason | <GAP> | I | went | 2 | te | store | wuz | 2 | buy | <GAP> | fud |
+-------+--------+-------+---+------+----+-----+-------+-----+----+-----+-------+------+
The special GAP characters are fine.
However, what is in-efficient about Needle Wunsch is that people who wrote the algorithm believed that the order of the gap characters was important. The following are computed as two separate cases:
ALIGNMENT ONE
+---+-------+-------+---+---+
| A | 1 | <GAP> | R | A |
+---+-------+-------+---+---+
| A | <GAP> | B | R | A |
+---+-------+-------+---+---+
ALIGNMENT TWO
+---+-------+-------+---+---+
| A | <GAP> | 1 | R | A |
+---+-------+-------+---+---+
| A | B | <GAP> | R | A |
+---+-------+-------+---+---+
However, if you have two or more gaps in a row, then order of the gaps should not matter.
The Needleman-Wunch algorithm calculates the same thing many times over because whoever wrote the algorithm thought that order mattered a little more than it really does.
The following two alignments have the same score.
Also, both alignments have more or less the same meaning in the "real world" (outside of the computer).
However, the Needleman-Wunch algorithm will compute the scores of the two example alignments twice instead of computing it only one time.

python: (calling all experts out there to help) how do i write a chatbot which can commands and execute a python function?

i was going through chatterbot, NLTK libraries writeups but i just could not find a way where i provide an english like command and the response can be a python function.
For example: i could say "Get me all sales numbers for August in the Delhi", it should pick words from it and do a dataframe query to fetch me the data. and similar intelligence.
In summary, i will speak to data in english and it should convert into relevant dataframe command to get me the data.
any thoughts ?

Well one suggestion is to use NLP Linguistic Features
For ease, i will be using spacy
import spacy
nlp = spacy.load('en_core_web_md')
doc = nlp('Get me all sales numbers for August in the Delhi')
for token in doc:
print(token.text,token.dep_,token.pos_)
Output
| 'Word' | 'DEPENDENY' | 'POS' |
----------------------------------
|'Get' | 'ROOT' | 'AUX' |
|'me', | 'dative' | 'PRON' |
|'all' | 'det' | 'DET' |
|'sales' | 'compound' | 'NOUN' |
|'numbers'| 'dobj' | 'NOUN' |
|'for' | 'prep' | 'ADP' |
|'August' | 'pobj' | 'PROPN'|
|'in' | 'prep' | 'ADP' |
|'the' | 'det' | 'DET' |
|'Delhi' | 'pobj' | 'PROPN'|
Here you can use these attributes extracted such as pos tagging and dependency to get your desired value e.g
df[DEPENDENY.compound].mean()
You can devise more NLP techniques such as entity recognition and based on that you can move further to create queries. This may take an in-depth thinking for logic formulation but u need to explore more and write some rules.

Is there a way to add a new line after every ']' in Python?

I originally had a string containing BBCode in which I wanted to format it better so it can be readable.
I had something like
['"9-5[centre][notice][url=https:\\/\\/www.youtube.com\\/playlist?list=PL3OTylWB5pG7s7JowIUEYBiPkKR0GRRRG][b]\\u25ba osu! Mapping Theory[\\/b][\\/url]\\n[url=https:\\/\\/youtu.be\\/0uGeZzyobSY]Linear Momentum[\\/url] | [url=https:\\/\\/youtu.be\\/zOzi8Q655vs]Linear Momentum 2[\\/url] | [url=https:\\/\\/youtu.be\\/Rm5l0UDJLcQ]Angular Momentum and Circular Flow[\\/url] | [url=https:\\/\\/youtu.be\\/hRc3Xm0wI7s]Active and Passive Mapping[\\/url]\\n[url=https:\\/\\/youtu.be\\/OgNhsZpKRYc]Slider Flow[\\/url] | [url=https:\\/\\/youtu.be\\/e05hOKXfWOk]Stream Flow[\\/url] | [url=https:\\/\\/youtu.be\\/zYAujNMPVbY]Slider Mechanics[\\/url] | [url=https:\\/\\/youtu.be\\/ZOtkAQ3MoNE]Aesthetics by Symmetry[\\/url] | [url=https:\\/\\/youtu.be\\/WnLG31LaQx0]Aesthetics by Complexity[\\/url] | [url=https:\\/\\/youtu.be\\/i323hh7-CAQ]Defining Flow[\\/url]\\n[url=https:\\/\\/youtu.be\\/hNnF5NLoOwU]Flow and Aesthetics[\\/url] | [url=https:\\/\\/youtu.be\\/tq8fu_-__8M]Angle Emphasis[\\/url] | [url=https:\\/\\/youtu.be\\/6ilBsa_dV8k]Strain[\\/url] | [url=https:\\/\\/youtu.be\\/KKDnLsIyRp0]Pressure[\\/url] | [url=https:\\/\\/youtu.be\\/jm43HilQhYk]Tension[\\/url] | [url=https:\\/\\/youtu.be\\/-_Mh0NbpHXo]Song Choice[\\/url] | [url=https:\\/\\/youtu.be\\/BNjVu8xq4os]Song Length[\\/url]\\n\\n[url=https:\\/\\/www.youtube.com\\/playlist?list=PL3OTylWB5pG6t5MCwGnq87iYZnE5G7aZL][b]\\u25ba osu! Rambling[\\/b][\\/url]\\n[url=https:\\/\\/youtu.be\\/-Beeh7dKyTk]Storyboards[\\/url] | [url=https:\\/\\/youtu.be\\/i6zzHMzwIzU]Why[\\/url]\\n\\n[url=https:\\/\\/youtu.be\\/_sBP7ttRQog]0 BPM[\\/url] | [url=https:\\/\\/youtu.be\\/UgtR6WnuTT8]ppv2 Pt.1[\\/url] | [url=https:\\/\\/youtu.be\\/Bx14u5tltyE]ppv2 Pt.2[\\/url] | [url=https:\\/\\/youtu.be\\/-095yuSLE4Y]Super high star rating[\\/url][\\/notice][url=https:\\/\\/amo.s-ul.eu\\/oApvJHWA][b]Skin v3.4[\\/b][\\/url]\\n[size=85]Personal edit of [url=https:\\/\\/osu.ppy.sh\\/forum\\/t\\/481314]Re:m skin by Choilicious[\\/url][\\/size]\\n\\n[img]http:\\/\\/puu.sh\\/qqv6C\\/0aaca52f51.jpg[\\/img][url=https:\\/\\/osu.ppy.sh\\/u\\/Satellite][img]http:\\/\\/puu.sh\\/qqv6K\\/94681bed3f.jpg[\\/img][\\/url][url=https:\\/\\/osu.ppy.sh\\/u\\/Sellenite][img]http:\\/\\/puu.sh\\/qqv6T\\/c943ed1703.jpg[\\/img][\\/url][url=https:\\/\\/osu.ppy.sh\\/u\\/Morinaga][img]http:\\/\\/puu.sh\\/qqv70\\/cfbdb2a242.jpg[\\/img][\\/url][url=https:\\/\\/osu.ppy.sh\\/u\\/-Mo-][img]http:\\/\\/puu.sh\\/qqv77\\/ca489f2d00.jpg[\\/img][\\/url]\\n[notice]I don\'t really do nomination stuff often anymore. \\nHowever, please do show me your map if it\'s any of the following:[box=][b]Bounty[\\/b]\\n[size=50]High priority modding for these artists\\/songs (maybe a GD, just ask).\\nPreferably non-cut versions and songs that have no ranked maps yet.[\\/size]\\n\\nYuuhei Satellite\\nYuuhei Catharsis\\nShoujo Fractal\\nHoneyWorks (non-vocaloid)\\nTrySail\\nClariS\\n\\nClariS - CLICK (Asterisk DnB Remix), [size=85]either version.[\\/size]\\nfhana - Outside of Melancholy, [size=85]a version that isn\'t cut pls[\\/size]\\nAny cover of \\u7832\\u96f7\\u6483\\u6226\\u3001\\u59cb\\u3081![\\/box]I also do storyboard checks for any map.\\n\\nPMs are open for anything. Ask me anything. \\nAsk me what my favourite colour is if you really want even.[\\/notice][box=Guests][b]Ranked[\\/b]\\n[url=https:\\/\\/osu.ppy.sh\\/b\\/1575100][img]http:\\/\\/s.ppy.sh\\/images\\/insane.png[\\/img] senya - Terasareru kurai no Shiawase [Lunatic][\\/url]\\n[url=https:\\/\\/osu.ppy.sh\\/b\\/1794557][img]http:\\/\\/s.ppy.sh\\/images\\/insane.png[\\/img] senya - Arehateta Chijou no Uta [Collab Insane][\\/url]\\n[url=https:\\/\\/osu.ppy.sh\\/b\\/1592915][img]http:\\/\\/s.ppy.sh\\/images\\/insane.png[\\/img] Tanaka Hirokazu - C-TYPE [TetriS-TYPE] [S-TYPE][\\/url]\\n[url=https:\\/\\/osu.ppy.sh\\/b\\/1490130][img]http:\\/\\/s.ppy.sh\\/images\\/insane.png[\\/img] TrySail - adrenaline!!! [Insane][\\/url] [size=85]Slightly ruined version.[\\/size]\\n[url=https:\\/\\/osu.ppy.sh\\/b\\/1401096][img]http:\\/\\/s.ppy.sh\\/images\\/insane.png[\\/img] senya - Shunkan Everlasting [Insane][\\/url]\\n[url=https:\\/\\/osu.ppy.sh\\/b\\/795269][img]
Basically unreadable currently.
I tried making it look like
['"9-5[centre][notice][url=https:\\/\\/www.youtube.com\\/playlist?list=PL3OTylWB5pG7s7JowIUEYBiPkKR0GRRRG]
[b]
\\u25ba osu! Mapping Theory[\\/b]
[\\/url]\\n[url=https:\\/\\/youtu.be\\/0uGeZzyobSY]
Linear Momentum[\\/url]
| [url=https:\\/\\/youtu.be\\/zOzi8Q655vs]
Linear Momentum 2[\\/url]
| [url=https:\\/\\/youtu.be\\/Rm5l0UDJLcQ]
Angular Momentum and Circular Flow[\\/url]
| [url=https:\\/\\/youtu.be\\/hRc3Xm0wI7s]
Active and Passive Mapping[\\/url]
\\n[url=https:\\/\\/youtu.be\\/OgNhsZpKRYc]
Slider Flow[\\/url]
| [url=https:\\/\\/youtu.be\\/e05hOKXfWOk]
Stream Flow[\\/url]
| [url=https:\\/\\/youtu.be\\/zYAujNMPVbY]
Slider Mechanics[\\/url]
| [url=https:\\/\\/youtu.be\\/ZOtkAQ3MoNE]
Aesthetics by Symmetry[\\/url]
| [url=https:\\/\\/youtu.be\\/WnLG31LaQx0]
Aesthetics by Complexity[\\/url]
| [url=https:\\/\\/youtu.be\\/i323hh7-CAQ]
Defining Flow[\\/url]
\\n[url=https:\\/\\/youtu.be\\/hNnF5NLoOwU]
Flow and Aesthetics[\\/url]
| [url=https:\\/\\/youtu.be\\/tq8fu_-__8M]
Angle Emphasis[\\/url]
| [url=https:\\/\\/youtu.be\\/6ilBsa_dV8k]
Strain[\\/url]
| [url=https:\\/\\/youtu.be\\/KKDnLsIyRp0]
Pressure[\\/url]
| [url=https:\\/\\/youtu.be\\/jm43HilQhYk]
Tension[\\/url]
| [url=https:\\/\\/youtu.be\\/-_Mh0NbpHXo]
Song Choice[\\/url]
|
Where there's a new line after every ']'
I've tried tweaking re.sub("[\(\[].*?[\)\]]", "", str(x)) to fit what I need but it just deletes everything inside of them. (I have no idea how regex works)
How can I go about this?

There's no need for a regular expression, just use the simple str.replace() function.
x = x.replace(']', ']\n')

It really depends on exactly what you want your output to look like.
I interpreted your output as wanting a newline after each url= tag, which would require the following regex:
output = re.sub(r"(\[url.*?\])", r"\1\n", input)
The brackets () form a capture group which is then used in the replace statement as \1 since its the first unnamed capture group.
You can change the regex to your will but just keep the stuff you want to keep within the capture group.
If you want to experiment with regex you can use https://regexr.com/ which is an amazing resource when fiddling around with regex.

How do I print a specific part of a YAML string

My YAML database:
left:
- title: Active Indicative
fill: "#cb202c"
groups:
- "Present | dūc[ō] | dūc[is] | dūc[it] | dūc[imus] | dūc[itis] | dūc[unt]"
My Python code:
import io
import yaml
with open("C:/Users/colin/Desktop/LBot/latin3_2.yaml", 'r', encoding="utf8") as f:
doc = yaml.safe_load(f)
txt = doc["left"][1]["groups"][1]
print(txt)
Currently my output is Present | dūc[ō] | dūc[is] | dūc[it] | dūc[imus] | dūc[itis] | dūc[unt] but I would like the output to be ō, is, it, or imus. Is this possible in PyYaml and if so how would I implement it? Thanks in advance.

I don't have a PyYaml solution, but if you already have the string from the YAML file, you can use Python's regex module to extract the text inside the [ ].
import re
txt = "Present | dūc[ō] | dūc[is] | dūc[it] | dūc[imus] | dūc[itis] | dūc[unt]"
parts = txt.split(" | ")
print(parts)
# ['Present', 'dūc[ō]', 'dūc[is]', 'dūc[it]', 'dūc[imus]', 'dūc[itis]', 'dūc[unt]']
pattern = re.compile("\\[(.*?)\\]")
output = []
for part in parts:
match = pattern.search(part)
if match:
# group(0) is the matched part, ex. [ō]
# group(1) is the text inside the (.*?), ex. ō
output.append(match.group(1))
else:
output.append(part)
print(" | ".join(output))
# Present | ō | is | it | imus | itis | unt
The code first splits the text into individual parts, then loops through each part search-ing for the pattern [x]. If it finds it, it extracts the text inside the brackets from the match object and stores it in a list. If the part does not match the pattern (ex. 'Present'), it just adds it as is.
At the end, all the extracted strings are join-ed together to re-build the string without the brackets.
EDIT based on comment:
If you just need one of the strings inside the [ ], you can use the same regex pattern but use the findall method instead on the entire txt, which will return a list of matching strings in the same order that they were found.
import re
txt = "Present | dūc[ō] | dūc[is] | dūc[it] | dūc[imus] | dūc[itis] | dūc[unt]"
pattern = re.compile("\\[(.*?)\\]")
matches = pattern.findall(txt)
print(matches)
# ['ō', 'is', 'it', 'imus', 'itis', 'unt']
Then it's just a matter of using some variable to select an item from the list:
selected_idx = 1 # 0-based indexing so this means the 2nd character
print(matches[selected_idx])
# is

Tabbing in Python?

I need to write data to a textfile as a table. Sort of like a database. The header has Drivers, Cars, Teams, Grids, Fastest Lap, Race Time and Points. When I try to write the data that goes under it the don't line up. As some drivers names are longer than others.
It looks a bit like this:
| Driver |
|Sebastian William|
|Tom Hamilton |
Only 2 of the names actually align with the header. I am only trying to solve the issue with Drivers for now once I figure that out I should be able to gets all the other headers lined up.
Using a for loop through the array of dictionaries I set x to equal the len of the drivers name and 22 is the length of the longest name(18) plus a few spaces.
TextFile.write((items['Driver']+'\t|').expandtabs(22-x))
Any way of making them line up?

You could use format string syntax:
>>> "|{:22}|".format("Niki Lauda")
'|Niki Lauda |'
You can also change the alignment:
>>> "|{:>22}|".format("Niki Lauda")
'| Niki Lauda|'
>>> "|{:^22}|".format("Niki Lauda")
'| Niki Lauda |'
and if you want more flexibility with your column size, you can parametrize that as well:
>>> "|{:^{}}|".format("Niki Lauda", 24)
'| Niki Lauda |'

On top of the answer provided by Tim, you could opt to use Tabulate which is very easy to use and customise.
table = [["spam",42],["eggs",451],["bacon",0]]
headers = ["item", "qty"]
print tabulate(table, headers, tablefmt="grid")
+--------+-------+
| item | qty |
+========+=======+
| spam | 42 |
+--------+-------+
| eggs | 451 |
+--------+-------+
| bacon | 0 |
+--------+-------+
This provides support for multiple different database styles too. I prefer this to simply using format because it allows me to completely change the output style by configuring the tablefmt argument.