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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 CheckForBadCharacters(filename, lines, error):
 """Logs an error for each line containing bad characters. Two kinds of bad characters: 1. Unicode replacement characters: These indicate that either the file contained invalid UTF-8 (likely) or Unicode replacement characters (which it shouldn't). Note that it's possible for this to throw off line numbering if the invalid UTF-8 occurred adjacent to a newline. 2. NUL bytes. These are problematic for some tools. Args: filename: The name of the current file. lines: An array of strings, each representing a line of the file. error: The function to call with any errors found. """

  for linenum, line in enumerate(lines):
    if u'\ufffd' in line:
      error(filename, linenum, 'readability/utf8', 5,
            'Line contains invalid UTF-8 (or Unicode replacement character).')
    if '\0' in line:
      error(filename, linenum, 'readability/nul', 5, 'Line contains NUL byte.')