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Can i create a list column in SQLAlchemy

I want to input the content of a text area and want to output it on another page but seems like there is nothing like multiline-text area in Flask. When I do the following
content = request.form['content']
it returns a string with line breaks as '\n' but when I try to output that content with replacing \n with or
, it doesn't seem to work.
So I thought I can store the multiline content in the form of a list.
So is there db column for the list, something like
content = db.Column(db.list(String))
or is there any other alternative.

Just to clarify, to the computer these 2 text examples are exactly equivalent:
myString = """Hello
World
"""
myString = "Hello\nWorld"
We can confirm this by checking the repr value for both versions
repr(myString)
# 'Hello\nWorld'
Whether or not the formatting is performed in a "friendly way" where the newlines are rendered as such, is entirely dependent on how you choose to display them. In HTML, newlines are denoted with a <br> tag, so one option would be to store the actual HTML-formatted string in your database after inserting them. However, this may pose a security hazard by either allowing malicious links to be made clickable, or by allowing Javascript snippets to be executed when rendering the page.
The simplest solution would be to use the HTML <pre> tag, which tells it that you have already handled the formatting ahead-of-time. Using the same myString value as before, we can display it nicely with
<pre>
{{ myString }}
<pre>
using the Jinja2 syntax, as long as we pass this string to the render_template function, for example
#app.route("/")
def index():
myString = "Hello\nWorld"
return render_template("index.html", myString=myString)

How to extract long URL from email with Python?

I need to extract a very long URL (example below) from an email message that I grab using Gmail's IMAP.
https://example.com/account/resetpassword?code=e8EkT%2B48uMCHr3Sq4QZVr0%2FVHrTBwQvhYwubjeaKozn29I7VGvWSYNO6VNRLXCK230P%2FklDrFC6BpPI7OF%2F5yawHlux80jqTBhTq2QRS4r7sEnSM9qKV1mIXkTzx%2B5tjakgElg%3D%3D&returnUrl=example.com
However, when I try to print the grabbed message, I notice that my long URL has some extra things like =\r\n and 3D inside of it (see examples below) or it is split in several lines by =.
https://example.com/account/resetpa=\r\nssword?code=3De8EkT%2B48uMCHr3Sq4QZVr0%2FVHrTBwQvhYwubjeaKozn29I7VGvWSYNO6V=\r\nNRLXCK230P%2FklDrFC6BpPI7OF%2F5yawHlux80jqTBhTq2QRS4r7sEnSM9qKV1mIXkTzx%2B5=\r\ntjakgElg%3D%3D&returnUrl=3Dexample.com
https://example.com/account/resetpa=
ssword?code=3De8EkT%2B48uMCHr3Sq4QZVr0%2FVHrTBwQvhYwubjeaKozn29I7VGvWSYNO6V=
NRLXCK230P%2FklDrFC6BpPI7OF%2F5yawHlux80jqTBhTq2QRS4r7sEnSM9qKV1mIXkTzx%2B5=
tjakgElg%3D%3D&returnUrl=3Dexample.com
How can I make sure that nothing is added to the long URL so that I could use it later to open?

I believe that format with = and 3D is called quoted printable. https://en.wikipedia.org/wiki/Quoted-printable
You could try using quopri.decodestring(string). https://docs.python.org/2/library/quopri.html

"\r\n" is a carriage return, which you can get rid of by using urlstring.replace("\r\n", ""). %3D means =(source), but I don't see why this would be an issue for you. The only issue is the carriage returns, which print your URL on different lines.

url_for creates a url query string with &

Lets say i have the following script in a html template of a flask application
<script type="text/javascript">
console.log('{{ url_for('root', arg1='hello', arg2='world') }}')
<script>
and i have a flask endpoint root()
#app.route('/', methods=['GET'])
def root():
print(print(request.args))
when i call my page the internal script is rendered to
console.log('/api/art_structure?arg2=world&arg1=hello')
When I call this url my request.args dict is:
ImmutableMultiDict([('amp;arg1', 'hello'), ('arg2', 'world')])
Which is not correct since the key of arg1 is wrong.
Any clues how I can prevent jinja2 from converting & to &?

The ampersand
The correct URL is /api/art_structure?arg2=world&arg1=hello.
The problem with the above URL is that ampersand (&) cannot be written directly in HTML, because the ampersand is used for entity references. For example, to write < character in HTML, which is not a tag start, one can write <. Because of that, to write &, one should escape it, i.e. write it as &.
Jinja2 templating engine does that by default. So, you can dump the contents of any string variable even if it contains special characters and they will be correctly escaped, e.g. & will become & as in your case.
How does that work?
So, if you actually put this in your jinja template: link, it would write the following HTML code: link, and if you clicked on the link in the browser, it would correctly replace & with & and open /api/art_structure?arg2=world&arg1=hello.
(note, however, that writing plain & as it is into HTML may sometimes also work, because browsers may guess how to fix the error)
So why does it not simply work in this case?
Because you are generating JavaScript and not HTML (you are generating code within <script> and </script>. In JavaScript, & is fine and should not be escaped, so you are free to write it as it is. To tell Jinja that you do not want it to escape the string, you can use the safe filter, i.e. {{ url_for('root', arg1='hello', arg2='world') | safe}}.

Try using safe
Ex:
console.log("{{ url_for('root', arg1='hello', arg2='world') | safe}}")
MoreInfo

Python, return new line in function return

I have code like this `
celldata=""
count=0
for tableData in y:
count = count+1
strcount=str(count)
celldata += strcount + ")" + tableData .text + "\n"
return celldata
`
I am returning the value to be used in flask, the issue is I want each for loop row in a new line but after trying \n, and in the flask web app I am getting celldata in one single line with one space each between each output line of the for loop.
Here is my current output for celldata in flask web
1)xxxx 2)yyyy
I want the flask web url to return
1)xxxx
2)yyyy

You're presumably returning HTML, and viewing that HTML in a browser.
In HTML, all runs of whitespace are equivalent—there's no difference between '\n' and ' '. The browser should convert them all to single spaces, and then decide how to flow the results nicely.
So, you're going to have to learn some basic HTML. But here are a few quick hints to get you started:
<p>one paragraph</p> <p>another paragraph</p> defines two separate paragraphs.
<p>one paragraph<br />with a line break in the middle</p> defines a paragraph with a line break in the middle.
<table><tr><td>row one</td></tr> <tr><td>row two</td></tr></table> defines a table of two rows (and one column).
The last one is the most complicated, but given that you've got things named tableData and celldata, I suspect it may be what you actually want here.
HTML itself only specifies "structure", not layout. It's up to the browser to decide what "two paragraphs" or "a line break" or "two rows" actually means in terms of actual pixels. If you want finer control, you need to learn CSS as well as HTML, which lets you specify explicit styles for these elements.

If you are trying to format this as HTML, I would suggest you add <br /> also to the returned text:
celldata = []
for count, tableData in enumerate(y, start=1):
celldata.append('{}) {}<br/>'.format(count, tableData.text))
return '\n'.join(celldata)
This first builds a list of entries with the correct numbering, and then joins each line together with a newline. The newline is purely cosmetic and will only effect how the HTML appears when viewed as source. It is the <br /> which will ensure each entry appears on a different line.
enumerate() is used to automatically count your entries for you.

How do I preserve new lines when extracting text from html using lxml.text_content()

I am trying to learn to use Whoosh. I have a large collection of html documents I want to search. I discovered that the text_content() method creates some interesting problems for example I might have some text that is organized in a table that looks like
<html><table><tr><td>banana</td><td>republic</td></tr><tr><td>stateless</td><td>person</td></table></html>
When I take the original string and and get the tree and then use text_content to get the text in the following manner
mytree = html.fromstring(myString)
text = mytree.text_content()
The results have no spaces (as should be expected)
'bananarepublicstatelessperson'
I tried to insert new lines using string.replace()
myString = myString.replace('</tr>','</tr>\n')
I confirmed that the new line was present
'<html><table><tr><td>banana</td><td>republic</td></tr>\n<tr><td>stateless</td><td>person</td></table></html>'
but when I run the same code from above the line feeds are not present. Thus the resulting text_content() looks just like above.
This is a problem from me because I need to be able to separate words, I thought I could add non-breaking spaces after each td and line breaks after rows as well asd line breaks after body elements etc to get text that reasonably conforms to my original source.
I will note that I did some more testing and found that line breaks inserted after paragraph tag closes were preserved. But there is a lot of text in the tables that I need to be able to search.
Thanks for any assistance

You could use this solution:
import re
def striphtml(data):
p = re.compile(r'<.*?>')
return p.sub('', data)
>>> striphtml('I Want This <b>text!</b>')
>>> 'I Want This text!'
Found here: using python, Remove HTML tags/formatting from a string