def concatenate(input_files, output_file):
from .modules import utils, concat<EOL>if not isinstance(input_files, (list, tuple)):<EOL><INDENT>raise RuntimeError('<STR_LIT>')<EOL><DEDENT>return {<EOL>'<STR_LIT>': utils.no_dependencies,<EOL>'<STR_LIT>': concat.concatenate_input_files,<EOL>'<STR_LIT:input>': input_files,<EOL>'<STR_LIT>': output_file,<EOL>'<STR_LIT>': {},<EOL>}<EOL>
Concatenates the input files into the single output file.

In debug mode this function adds a comment with the filename
before the contents of each file.