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   Tom and his father are playing in the playground. There is a cat and a dog there. They are playing with a ball together. “I think the cat is older than the dog," Tom says, “I don't think so," his father says. “Why?" “Because the dog looks bigger than the cat " Tom laughs and says, "But I like the cat. It is white and it is funnier than the dog. "Tom's father says, “Dogs are my favourite animals because they are very friendly to me" "Yes, but I like smaller ones. Can we keep one?" Tom says. "Of course," Tom's father says.

$a$为常数，$\forall x\in R$，$f\left(x\right)=a^2{x}^2+ax+1>0$，则$a$的取值范围是（   ）