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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 CheckDefaultLambdaCaptures(filename, clean_lines, linenum, error):
 """Check that default lambda captures are not used. Args: filename: The name of the current file. clean_lines: A CleansedLines instance containing the file. linenum: The number of the line to check. error: The function to call with any errors found. """

  line = clean_lines.elided[linenum]

  # A lambda introducer specifies a default capture if it starts with "[="
  # or if it starts with "[&" _not_ followed by an identifier.
  match = Match(r'^(.*)\[\s*(?:=|&[^\w])', line)
  if match:
    # Found a potential error, check what comes after the lambda-introducer.
    # If it's not open parenthesis (for lambda-declarator) or open brace
    # (for compound-statement), it's not a lambda.
    line, _, pos = CloseExpression(clean_lines, linenum, len(match.group(1)))
    if pos >= 0 and Match(r'^\s*[{(]', line[pos:]):
      error(filename, linenum, 'build/c++11',
            4,  # 4 = high confidence
            'Default lambda captures are an unapproved C++ feature.')