Same file type, different icon. How to reset it

I have a folder with Python source code. All files are being opened with double click with Text Editor, also the "problematic" one. All files have .py extension.

The "problematic" file has a green Qt icon and I didn't find a way to remove it. Reset and set default application (that now is Text Editor) didn't help.

Ubuntu 20.04

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$ file -i MyHTMLParser.py 
MyHTMLParser.py: text/x-python; charset=us-ascii

$ file MyHTMLParser.py 
MyHTMLParser.py: Python script, ASCII text executable

$ file -i Scanner.py 
Scanner.py: text/x-python; charset=utf-8

$ file Scanner.py 
Scanner.py: Python script, UTF-8 Unicode text executable, with CRLF line terminators

First line of MyHTMLParser.py:

from html.parser import HTMLParser

First line of Scanner.py:

from PyQt5 import QtCore

text/x-qml MIME type is shown from Properties

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That type is not present in

/etc/mime.types

I really can't understand where that information is stored.

UPDATED 'N'

I wrote a script that remove all \r\n line endings and UTF-8 characters. Now Scanner_new.py has the same type of MyHTMLParser.py, but nothing is changed:

$ file -i MyHTMLParser.py 
MyHTMLParser.py: text/x-python; charset=us-ascii

$ file MyHTMLParser.py 
MyHTMLParser.py: Python script, ASCII text executable

$ file -i Scanner_new.py 
Scanner_new.py: text/x-python; charset=us-ascii

$ file Scanner_new.py 
Scanner_new.py: Python script, ASCII text executable

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Solution 1:

I found the solution. The problem isn't the line ending or the characters set (UTF-8, ASCII...). If in the file there is the sentence "import QtCore" (never mind if as start line or in the middle of the file) the icon will be the Qt one.

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