Adding metadata Leave feedback

def run():
    files = os.listdir(constants.input_path)
    for file in files:
        with gm.Metadata(constants.input_path+file) as metadata:
            if metadata.file_format != gm.common.FileFormat.UNKNOWN and metadata.get_document_info().is_encrypted != True:
                print()
                print(file)
				
				# Add a property containing the file last printing date if it's missing
                # Note that the property will be added to metadata packages that satisfy the following criteria:
                # 1) Only existing metadata packages will be affected. No new packages are added during this operation
                # 2) There should be a known metadata property in the package structure that fits the search condition but is actually missing in the package.
                # All properties supported by a certain package are usually defined in the specification of a particular metadata standard
				
                specification = gm.search.ContainsTagSpecification(gm.tagging.Tags.time.printed)
                now = datetime.now()
                property_value = gm.common.PropertyValue(now)
                affected = metadata.add_properties(specification, property_value)
                print(f"Affected properties: {affected}");
                filename, file_extension = os.path.splitext(file)
                metadata.save(constants.output_path + "output" + file_extension)