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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 GetUsedMemory(self):
 """Retrieves the amount of memory used by the process. Returns: int: amount of memory in bytes used by the process or None if not available. """

    try:
      memory_info = self._process.memory_info()
    except psutil.NoSuchProcess:
      return None

    # Psutil will return different memory information depending on what is
    # available in that platform.
    memory_data = getattr(memory_info, 'data', 0)
    memory_shared = getattr(memory_info, 'shared', 0)

    return memory_data + memory_shared