For the record, I was able to search pypi and find a package that worked. I installed abcplus pip install abcplus and that allowed me to execute the import statement.

I'm assuming that you're following this tutorial?

The mistake that you've made (and to be fair, the tutorial is unclear on this), is assuming that abc_base is the name of some module that lives inside the standard library.

Rather, it just happens to be the name of the very first python file in the tutorial, in which the PluginBase class is defined.

To adapt the code to work for you, you need to import from whatever file contains your desired base class, rather than from abc_base.

Note: Because the class names and file names are identical in your example, I went ahead and changed the file names to make it clearer what's happening and what you need to import:

base.py

import abc

# Note: You forgot to capitalize the 'A' in the original
class AbstractBaseClass(object):
    __metaclass__ = abc.ABCMeta

    @abc.abstractmethod
    def load(self, input):
    """Retrieve data from the input source and return an object."""
        return

concrete.py

from base import AbstractBaseClass

class ConcreteChildClass(AbstractBaseClass):
    def load(self, input):
        return input.read()