code: def envGet(self, name, default=None, conv=None):
          
          if self._env.has_key(name):
              if conv is not None:
                  return conv(self._env.get(name))
              else:
                  return self._env.get(name)
          else:
              return default
docs: Return value for environment variable or None.  
          
          @param name:    Name of environment variable.
          @param default: Default value if variable is undefined.
          @param conv:    Function for converting value to desired type.
          @return:        Value of environment variable.