==== REQUIRED BASIC INFO OF YOUR IREDMAIL SERVER ====
- iRedMail version (check /etc/iredmail-release): 1.3.2
- Deployed with iRedMail Easy or the downloadable installer? Upgraded from iRedadmin-pro 2.4.1 (MySQL)
- Linux/BSD distribution name and version: centos 7.9
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): MySQL
- Web server (Apache or Nginx): nginx
- Manage mail accounts with iRedAdmin-Pro? yes
- [IMPORTANT] Related original log or error message is required if you're experiencing an issue.
====

Hello.

When i try to edit email account in iRedAdmin-Pro 4.6, I receive following error in web browser:
Error: JSONDecodeError('Expecting value: line 1 column 1 (char 0)',)

And following errors in mlmmjadmin logs:
mlmmjadmin[1143]: Traceback (most recent call last):
                                                          File "/usr/lib/python2.7/site-packages/web/application.py", line 239, in process
                                                            return self.handle()
                                                          File "/usr/lib/python2.7/site-packages/web/application.py", line 230, in handle
                                                            return self._delegate(fn, self.fvars, args)
                                                          File "/usr/lib/python2.7/site-packages/web/application.py", line 416, in _delegate
                                                            mod = __import__(mod, None, None, [''])
                                                          File "/opt/mlmmjadmin-3.0.4/controllers/subscriber.py", line 3, in <module>
                                                            from controllers.decorators import api_acl
                                                          File "/opt/mlmmjadmin-3.0.4/controllers/decorators.py", line 3, in <module>
                                                            from libs.utils import get_auth_token, api_render
                                                          File "/opt/mlmmjadmin-3.0.4/libs/utils.py", line 12
                                                            def str2bytes(s) -> bytes:
                                                                             ^
                                                        SyntaxError: invalid syntax

Python packages installed:

python-lxml-3.2.1-4.el7.x86_64
python2-dialog-3.3.0-6.el7.noarch
python-pycurl-7.19.0-19.el7.x86_64
python36-sqlalchemy-1.1.3-3.el7.x86_64
python-2.7.5-89.el7.x86_64
python-urllib3-1.10.2-7.el7.noarch
python-chardet-2.2.1-3.el7.noarch
python3-3.6.8-17.el7.x86_64
python2-psutil-5.6.7-1.el7.x86_64
python-enum34-1.0.4-1.el7.noarch
python36-chardet-3.0.4-1.el7.noarch
python36-crypto-2.6.1-16.el7.x86_64
python-urlgrabber-3.10-10.el7.noarch
python2-acme-1.9.0-1.el7.noarch
python-six-1.9.0-2.el7.noarch
newt-python-0.52.15-4.el7.x86_64
MySQL-python-1.2.5-1.el7.x86_64
python-markupsafe-0.11-10.el7.x86_64
python2-pyasn1-0.1.9-7.el7.noarch
python3-setuptools-39.2.0-10.el7.noarch
python-ndg_httpsclient-0.3.2-1.el7.noarch
python-slip-0.4.0-4.el7.noarch
python-pycparser-2.14-1.el7.noarch
python-backports-1.0-8.el7.x86_64
python-backports-ssl_match_hostname-3.5.0.1-1.el7.noarch
python36-six-1.14.0-2.el7.noarch
python36-requests-2.14.2-2.el7.noarch
python36-PyMySQL-0.9.3-1.el7.noarch
python36-dns-1.16.0-1.el7.noarch
python36-jinja2-2.11.1-1.el7.noarch
python2-josepy-1.3.0-2.el7.noarch
python2-configargparse-0.11.0-2.el7.noarch
python-html5lib-0.999-7.el7.noarch
python2-parsedatetime-2.4-6.el7.noarch
python-requests-toolbelt-0.8.0-3.el7.noarch
audit-libs-python-2.8.5-4.el7.x86_64
rpm-python-4.11.3-45.el7.x86_64
python-decorator-3.4.0-3.el7.noarch
python-babel-0.9.6-8.el7.noarch
python-jinja2-2.7.2-4.el7.noarch
python-sqlalchemy-0.9.8-2.el7.x86_64
uwsgi-plugin-python2-2.0.18-8.el7.x86_64
python-cherrypy-3.2.2-4.el7.noarch
python-idna-2.4-1.el7.noarch
python3-pip-9.0.3-8.el7.noarch
python-slip-dbus-0.4.0-4.el7.noarch
libsemanage-python-2.5-14.el7.x86_64
python36-urllib3-1.25.6-2.el7.noarch
uwsgi-plugin-python36-2.0.18-8.el7.x86_64
python3-wheel-0.31.1-5.el7_7.noarch
python36-simplejson-3.10.0-2.el7.x86_64
python2-pyrfc3339-1.1-3.el7.noarch
python-zope-component-4.1.0-5.el7.noarch
python2-future-0.18.2-2.el7.noarch
python-requests-2.6.0-10.el7.noarch
libselinux-python-2.5-15.el7.x86_64
python-iniparse-0.4-9.el7.noarch
python-configobj-4.7.2-7.el7.noarch
systemd-python-219-78.el7.x86_64
python-cffi-1.6.0-5.el7.x86_64
python-gobject-base-3.22.0-1.el7_4.1.x86_64
python-pyudev-0.15-9.el7.noarch
python2-bcrypt-3.1.6-2.el7.x86_64
python-dns-1.12.0-4.20150617git465785f.el7.noarch
python-netifaces-0.10.4-3.el7.x86_64
python-schedutils-0.4-6.el7.x86_64
python-ipaddress-1.0.16-2.el7.noarch
python3-libs-3.6.8-17.el7.x86_64
python-zope-interface-4.0.5-4.el7.x86_64
python-zope-event-4.0.3-2.el7.noarch
python-beautifulsoup4-4.4.1-1.el7.noarch
python36-idna-2.7-2.el7.noarch
python-perf-3.10.0-1160.2.2.el7.x86_64
python2-certbot-1.9.0-1.el7.noarch
python-ply-3.4-11.el7.noarch
python-setuptools-0.9.8-7.el7.noarch
python-IPy-0.75-6.el7.noarch
python2-cryptography-1.7.2-2.el7.x86_64
python2-mock-1.0.1-10.el7.noarch
python36-pysocks-1.6.8-7.el7.noarch
python36-markupsafe-0.23-3.el7.x86_64
python-libs-2.7.5-89.el7.x86_64
python2-distro-1.2.0-3.el7.noarch
python-linux-procfs-0.4.11-4.el7.noarch
python-firewall-0.6.3-11.el7.noarch
python2-six-1.9.0-0.el7.noarch
dbus-python-1.1.1-9.el7.x86_64
python-webpy-0.37-8.el7.noarch
policycoreutils-python-2.5-34.el7.x86_64

Please help me.