Error: ImportError: No module named boto (DynamoDB)

This error usually appears in Python applications where it's failing to import the boto3 library. Depending on your runtime, the solution is:

• When using Python 2:

      pip2.7 install boto
      # or
      pip install boto

• When using Python 3:

      pip install --upgrade --user boto3
      # or
      pip3 install boto

• On Ubuntu, you might also try using apt:

      apt install python-boto3