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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def files_size(fs0, fs1, files):
 """Gets the file size of the given files."""

    for file_meta in files['deleted_files']:
        file_meta['size'] = fs0.stat(file_meta['path'])['size']
    for file_meta in files['created_files'] + files['modified_files']:
        file_meta['size'] = fs1.stat(file_meta['path'])['size']

    return files