You can execute the SQL query generated by sqlsequencereset from within python in this way (using the default database):

from django.core.management.color import no_style
from django.db import connection

from myapps.models import MyModel1, MyModel2


sequence_sql = connection.ops.sequence_reset_sql(no_style(), [MyModel1, MyModel2])
with connection.cursor() as cursor:
    for sql in sequence_sql:
        cursor.execute(sql)

I tested this code with Python3.6, Django 2.0 and PostgreSQL 10.

I'm currently managing this by:

1. Using call_command to run sqlsequencereset
2. Grabbing the output into an in-memory StringIO object (instead of writing to a file on disc)
3. Executing the SQL directly against Django's default database

Code:

import io

from django.core.management import call_command
from django.db import connection


app_name = 'my_app'

# Get SQL commands from sqlsequencereset
output = io.StringIO()
call_command('sqlsequencereset', app_name, stdout=output, no_color=True)
sql = output.getvalue()
    
with connection.cursor() as cursor:
    cursor.execute(sql)

output.close()

also see [this gist][1], where it can be done e.g. from console for all apps.

import os

os.environ['DJANGO_COLORS'] = 'nocolor'

from django.core.management import call_command
from django.db import connection
from django.apps import apps
from io import StringIO

commands = StringIO()
cursor = connection.cursor()

for app in apps.get_app_configs():
    call_command('sqlsequencereset', app.label, stdout=commands)

cursor.execute(commands.getvalue())