encoder_1=LabelEncoder()

This is a line of code in Python that creates an instance of the LabelEncoder class from the scikit-learn library. The LabelEncoder is a utility class that can be used to transform categorical data into numerical data.

For example, if you have a dataset with a column of categorical data such as "red", "green", and "blue", you can use the LabelEncoder to transform these values into numerical values like 0, 1, and 2. This can be useful for machine learning algorithms that require numerical input.

Once the encoder has been created, you can use its fit_transform() method to transform your data. For example:

encoded_data = encoder_1.fit_transform(["red", "green", "blue", "red"])

This would result in the encoded_data variable containing the values [0, 1, 2, 0].