Who is she/he?

Today evening, when I got back from work, we found her/him in our backyard. First I thought this was a ground hog, but in closer inspection, it looks more like an overgrown rat. Can anyone identify?

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Update: Just found out. She is an Opossum. No wonder, she is quite lethargic! Unfortunately, most of the links I could find are for removal of them. Since she is in my backyard, I don’t care. She is not that ugly!