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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 _copy_files(source, target):
 """ Copy all the files in source directory to target. Ignores subdirectories. """

    source_files = listdir(source)
    if not exists(target):
        makedirs(target)
    for filename in source_files:
        full_filename = join(source, filename)
        if isfile(full_filename):
            shutil.copy(full_filename, target)