JOIN same table twice with aliases on SQLAlchemy

I figured this out. Here are the classes that are used in my Flask app:

class User(Model):
    id = db.Column(db.Integer, primary_key=True, autoincrement=True)
    username = Column(db.String(80), unique=True, nullable=False)
    skills = db.relationship('UserSkill')

class Skill(Model):
    id = db.Column(db.Integer, primary_key=True, autoincrement=True)
    name = Column(db.String(80))

class UserSkill(Model):
    status = db.Column(db.Enum(SkillStatus))
    user_id = db.Column(db.Integer, db.ForeignKey('users.id'), primary_key=True)
    skill_id = db.Column(db.Integer, db.ForeignKey('skills.id'), primary_key=True)
    skill = db.relationship("Skill")

So, the actual code would look like this:

from sqlalchemy.orm import aliased

userSkillF = aliased(UserSkill)
userSkillI = aliased(UserSkill)
skillF = aliased(Skill)
skillI = aliased(Skill)
            
db.session.query(User.id, User.username,\
         func.group_concat(func.distinct(skillF.name)).label('skills'),\
         func.group_concat(func.distinct(skillI.name)).label('other_skills')).\
    join(userSkillF, User.skills).\
    join(userSkillI, User.skills).\
    join(skillF, userSkillF.skill).filter(skillF.id.in_(skillIds)).\
    join(skillI, userSkillI.skill).\
    group_by(User.id).all()

Many thanks Ilja Everilä, fresh look on SqlAlchemy docs made me understand aliased now.