Error installing SQL server - Linux Mint

Question

I already have flask installed on my NOTEBOOK with Linux Mint, but still no module called flask is showing up along with dpkg error.

I tried various solutions on various websites such as:

1. sudo dpkg --configure -a
2. sudo apt-get install -f
3. sudo apt-get purge apache2 apache2-data apache2-utils

But every time I faced the same problem:

*Você quer continuar? [S/n] s
Configurando pgadmin4-apache2 (4.25-1.pgdg18.04+1) ...
apache2_invoke pgadmin4: already enabled
Traceback (most recent call last):
  File "setup.py", line 18, in <module>
    from pgadmin.model import db, User, Version, ServerGroup, Server, \
  File "/usr/share/pgadmin4/web/pgadmin/__init__.py", line 19, in <module>
    from flask import Flask, abort, request, current_app, session, url_for
ModuleNotFoundError: No module named 'flask'
dpkg: erro ao processar o pacote pgadmin4-apache2 (--configure):
 installed pgadmin4-apache2 package post-installation script subprocess returned error exit status 1
Erros foram encontrados durante o processamento de:
 pgadmin4-apache2
E: Sub-process /usr/bin/dpkg returned an error code (1)*