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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 fix_input_files(headerDir, sourceDir, containers=['vector', 'list', 'set', 'map'], seqType='both', verbose=False):
 """Fixes source- and header-files used as input when pre-processing MPL-containers."""

    # The new modification time.
    timestamp = datetime.datetime.now();
    # Fix the input files for containers in their variadic form.
    if seqType == "both" or seqType == "variadic":
        if verbose:
            print "Fix input files for pre-processing Boost.MPL variadic containers."
        fix_input_files_for_variadic_seq(headerDir, sourceDir, timestamp)
    # Fix the input files for containers in their numbered form.
    if seqType == "both" or seqType == "numbered":
        if verbose:
            print "Fix input files for pre-processing Boost.MPL numbered containers."
        fix_input_files_for_numbered_seq(headerDir, ".hpp", timestamp, containers)
        fix_input_files_for_numbered_seq(sourceDir, ".cpp", timestamp, containers)