How to Create a YAML File in Python

YAML, short for “YAML Ain’t Markup Language”, is a human-readable data serialization standard that can be used in conjunction with all programming languages. Its primary uses are for data exchange between languages with different data structures, storing data, and configuration files.

Python, being a powerful and flexible language, has several libraries to create and parse YAML files. This tutorial will guide you through how to create a YAML file using Python, specifically with the PyYAML library.

Step 1: Preparation

Before we write our Python code, you need to make sure that the PyYAML library is installed on your system. If it isn’t, install it by running the following command in your terminal/command-prompt:

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pip install pyyaml

If you encounter any problems with the pip, you can consult the official pip documentation for additional help.

Step 2: Start Writing the Python Code

After making sure you have installed PyYAML, you can start writing the Python code that will create a YAML file. First, you need to import the yaml module from PyYAML.

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import yaml

Step 3: Define the Data

Next, define the Python data that we wish to write to a YAML file. Let’s use a simple Python dictionary as an example:

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data = {
    'name': 'John Doe',
    'age': 30,
    'occupations': ['Developer', 'Freelancer']
}

Step 4: Create the YAML File

Next, it’s time to create the YAML file. We use the function yaml.dump() which does the conversion from Python dictionaries to YAML format. The converted YAML formatted data is then written to a file named ‘info.yaml’.

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with open('info.yaml', 'w') as file:
    documents = yaml.dump(data, file)

Full Python Code

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import yaml
 
data = {
    'name': 'John Doe',
    'age': 30,
    'occupations': ['Developer', 'Freelancer']
}
 
with open('info.yaml', 'w') as file:
    documents = yaml.dump(data, file)

The created YAML file (‘info.yaml’) will look like this:

age: 30
name: John Doe
occupations:
- Developer
- Freelancer

Conclusion

And that’s all there is to it! You’ve just created a YAML file using Python and PyYAML. This was a basic tutorial demonstrating how to store Python data structures such as dictionaries into readable YAML files.

Further exploration of the PyYAML library will yield ways to handle more complex data structures and even custom Python objects. Happy coding!