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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 edit_files(patterns, expressions=None, functions=None, executables=None, start_dirs=None, max_depth=1, dry_run=True, output=sys.stdout, encoding=None, newline=None):
 """Process patterns with MassEdit. Arguments: patterns: file pattern to identify the files to be processed. expressions: single python expression to be applied line by line. functions: functions to process files contents. executables: os executables to execute on the argument files. Keyword arguments: max_depth: maximum recursion level when looking for file matches. start_dirs: workspace(ies) where to start the file search. dry_run: only display differences if True. Save modified file otherwise. output: handle where the output should be redirected. Return: list of files processed. """

    if not is_list(patterns):
        raise TypeError("patterns should be a list")
    if expressions and not is_list(expressions):
        raise TypeError("expressions should be a list of exec expressions")
    if functions and not is_list(functions):
        raise TypeError("functions should be a list of functions")
    if executables and not is_list(executables):
        raise TypeError("executables should be a list of program names")

    editor = MassEdit(dry_run=dry_run, encoding=encoding, newline=newline)
    if expressions:
        editor.set_code_exprs(expressions)
    if functions:
        editor.set_functions(functions)
    if executables:
        editor.set_executables(executables)

    processed_paths = []
    for path in get_paths(patterns, start_dirs=start_dirs,
                          max_depth=max_depth):
        try:
            diffs = list(editor.edit_file(path))
            if dry_run:
                # At this point, encoding is the input encoding.
                diff = "".join(diffs)
                if not diff:
                    continue
                # The encoding of the target output may not match the input
                # encoding. If it's defined, we round trip the diff text
                # to bytes and back to silence any conversion errors.
                encoding = output.encoding
                if encoding:
                    bytes_diff = diff.encode(encoding=encoding, errors='ignore')
                    diff = bytes_diff.decode(encoding=output.encoding)
                output.write(diff)
        except UnicodeDecodeError as err:
            log.error("failed to process %s: %s", path, err)
            continue
        processed_paths.append(os.path.abspath(path))
    return processed_paths