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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 IsHFS(self):
 """Determines if the file system is HFS, HFS+ or HFSX. Returns: bool: True if the file system is HFS. """

    tsk_fs_type = self.GetFsType()
    return tsk_fs_type in [
        pytsk3.TSK_FS_TYPE_HFS, pytsk3.TSK_FS_TYPE_HFS_DETECT]