How To Import Model Files (.cto) Into Hyperledger Composer Playground For Testing
Step 1: Navigate to Playground
For this tutorial, I will be using IBM's hosted playground tool, but feel free to use your own local or hosted playground if you already have that set up. If you want to use the hosted playground, click here.

Step 2: Deploy a new business network
Click the "Deploy a new business network" button.
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Step 3: Configure your Business Network
Feel free to name your Business Network whatever you'd like, I'll be naming mine motel-five. Make sure to select empty-business-network. Then hit deploy.
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Step 4: Connect to your Business Network
Hit the "connect now" button.
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Step 5: Add your model.cto file
Now click the "Add a file.." button on the left-hand side. A modal will popup. Now add your model .cto file and click "Add".
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Step 6: Deploy changes
Hit the "Deploy changes" button on the bottom left-hand side.

Step 7: Enter the test section
Click the "test" tab. We will now be able to make a test transaction on our model file.
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Step 8: Create a test asset
Click the "Create New Asset" button. You will now be able to create a asset. I recommend playing with the numbers a little bit and making sure everything works as it's supposed to. If anything is off, you'll see an error pop up.
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