Dask bag read_sequence(...).map(...).compute() returning ValueError: too many values to unpack (expected 2)

Anonymous User

Hello everyone,
I would appreciate it if you can help me of what is wrong in my code. I have a list of objects, specifically ArcGIS items. My code is basically:

import dask.bag as db

def get_attribute(i):
    return i.title

bag = db.from_sequence(itms)
result = db.map(lambda x: get_attribute(x) , bag).compute()

Then I am getting this error:

ValueError: too many values to unpack (expected 2)

I thought maybe dask bag does not work with sequences of objects. It might be only for sequences of literal values. But I tried the same code with objects based on a simple class called Point:

class Point:
    def __init__(self, x, y):
        self.x = x
        self.y = y

    def get_x(self):
        return self.x
    
    def get_y(self):
        return self.y
######################
######################
def get_x(p):
    return p.get_x()
    
p1 = Point(1,2)
p2 = Point(-3,-1)
p3 = Point(0,0)

pnts = [p1,p2,p3]

bag = db.from_sequence(pnts)
result = db.map(lambda x: get_x(x) , bag).compute()

And it is working fine!!

So please let me know what I'am doing wrong.

Thank you so much.

Anonymous User

Anyone?