<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
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<USER_TASK:>
Description:
 def update_user_password(new_pwd_user_id, new_password,**kwargs):
 """ Update a user's password """

    #check_perm(kwargs.get('user_id'), 'edit_user')
    try:
        user_i = db.DBSession.query(User).filter(User.id==new_pwd_user_id).one()
        user_i.password = bcrypt.hashpw(str(new_password).encode('utf-8'), bcrypt.gensalt())
        return user_i
    except NoResultFound:
        raise ResourceNotFoundError("User (id=%s) not found"%(new_pwd_user_id))