Girish, In Python environments, you often need to install a package before you can import it. It makes the package available in the environment. Since you are operating in the context of some virtual machine when working in Watson Studio, you need to first "import" the package into your notebook environment, and then you can import the package in question. In your notebook, do this:
# First install the package into the notebook!pip install dash# Then import it inimport dashIn an environment on your local machine, you would just do the "pip install" without the leading exclamation (!), but since we are working ion the context of a Python notebook, we need to have the exclamation (!) to let the notebook know that we are executing a system level command.
# First install the package into the notebook
!pip install dash# Then import it inimport dash