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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 _ParseNamesString(self, names_string):
 """Parses the name string. Args: names_string (str):
 comma separated filenames to filter. """

    if not names_string:
      return

    names_string = names_string.lower()
    names = [name.strip() for name in names_string.split(',')]
    file_entry_filter = file_entry_filters.NamesFileEntryFilter(names)
    self._filter_collection.AddFilter(file_entry_filter)