## ReadFromText

When you create a pipeline, you often need to read data from some external source, such as a file or a database. Likewise, you may want your pipeline to output its result data to an external storage system. Beam provides read and write transforms for a number of common data storage types. If you want your pipeline to read from or write to a data storage format that isn’t supported by the built-in transforms, you can implement your own read and write transforms.

To read a PCollection from one or more text files, use beam.io.ReadFromText to instantiate a transform and specify the path of the file(s) to be read.

Kata: Read the 'countries.txt' file and convert each country name into uppercase.

Use beam.io.ReadFromText.
Refer to the Beam Programming Guide "Reading input data" section for more information.