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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 GetConfigValue(self, fieldName):
 """ Match given field name in Config table and return corresponding value. Parameters fieldName : string String matching Name column in Config table. Returns string or None If a match is found the corresponding entry in the Value column of the database table is returned, otherwise None is returned (or if multiple matches are found a fatal error is raised). """

    result = self._ActionDatabase("SELECT Value FROM Config WHERE Name=?", (fieldName, ))

    if result is None:
      return None
    elif len(result) == 0:
      return None
    elif len(result) == 1:
      goodlogging.Log.Info("DB", "Found database match in config table {0}={1}".format(fieldName, result[0][0]), verbosity=self.logVerbosity)
      return result[0][0]
    elif len(result) > 1:
      goodlogging.Log.Fatal("DB", "Database corrupted - multiple matches found in config table {0}={1}".format(fieldName, result))