select on sub query peewee - subquery

Question

I am wondering if I can do select() on sub_query.
I am able to do join sub_query with any peewee.Model. But when I wrote a sub_query and I wanted to just group by with one of the column
e.g. sub_query.select(sub_query.c.column_1, fn.COUNT(sub_query.c.column2)alias('col2_count')).group_by(sub_query.c.column_1)
query was not nested and was giving SQL syntax error.
(Can't reveal the code)
(I have done alias() on sub_query)
Edit
Example:
class Product(Model):
id = PrimaryKeyField()
name = CharField()
created_date = DateField()
class Part(Model):
id = PrimaryKeyField()
product = ForeignKeyField(Product)
name = CharField()
class ProductError(Model):
id = PrimaryKeyField()
product = ForeignKeyField(Product)
note = CharField()
class PartError(Model):
id = PrimaryKeyField()
part = ForeignKeyField(Part)
error = ForeignKeyField(ErrorMaster)
Here Product can have general error and
parts can have specific error which are predefined in ErrorMaster
I just want to know count of product which have errors against total products date wise. (error is product error or error in any part)
So sub_query is something like
sub_q = Product.select(
Product.created_date,
Product.id.alias('product_id'),
fn.IF(# checks if product has error
ProductError.is_null(True), if no product error check part error
fn.IF(fn.COUNT(PartError.id) == 0, 0, 1), # checks if error count > 0 then there is error in part
1
).alias('is_error')
).join(Part, on=Product.id == Part.product)
.join(ProductError, JOIN_LEFT_OUTER, on=Product.id == ProductError.product)
.join(PartError, JOIN_LEFT_OUTER, on=PartError.part == Part.id)
.where(Product.created_date.between(from_date, to_date))
.group_by(Product.id).alias('some_alias')
# below does not work but I can do this in sql
query = sub_q.select(sub_q.c.created_date,
fn.COUNT(sub_q.c.product_id).alias('total_products'),
fn.SUM(sub_q.c.is_error).alias('product_with_errors'))
.group_by(sub_q.c.created_date)