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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 _FormatExpression(self, frame, expression):
 """Evaluates a single watched expression and formats it into a string form. If expression evaluation fails, returns error message string. Args: frame: Python stack frame in which the expression is evaluated. expression: string expression to evaluate. Returns: Formatted expression value that can be used in the log message. """

    rc, value = _EvaluateExpression(frame, expression)
    if not rc:
      message = _FormatMessage(value['description']['format'],
                               value['description'].get('parameters'))
      return '<' + message + '>'

    return self._FormatValue(value)