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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 _GetUtf8Contents(self, file_name):
 """Check for errors in file_name and return a string for csv reader."""

    contents = self._FileContents(file_name)
    if not contents:  # Missing file
      return

    # Check for errors that will prevent csv.reader from working
    if len(contents) >= 2 and contents[0:2] in (codecs.BOM_UTF16_BE,
        codecs.BOM_UTF16_LE):
      self._problems.FileFormat("appears to be encoded in utf-16", (file_name, ))
      # Convert and continue, so we can find more errors
      contents = codecs.getdecoder('utf-16')(contents)[0].encode('utf-8')

    null_index = contents.find('\0')
    if null_index != -1:
      # It is easier to get some surrounding text than calculate the exact
      # row_num
      m = re.search(r'.{,20}\0.{,20}', contents, re.DOTALL)
      self._problems.FileFormat(
          "contains a null in text \"%s\" at byte %d" %
          (codecs.getencoder('string_escape')(m.group()), null_index + 1),
          (file_name, ))
      return

    # strip out any UTF-8 Byte Order Marker (otherwise it'll be
    # treated as part of the first column name, causing a mis-parse)
    contents = contents.lstrip(codecs.BOM_UTF8)
    return contents