Actually a slumped person 把 is shown. But the explanations use it as "doorhandle". This understanding is based on the character: 把 (bǎ, bà), which is in combination of a hand 扌 and means: doorknob.
Tip: Go to the radicals that are contained in this character and learn all the characters with this radical systematically!
Vocabulary
把握
bǎ wò
to grasp (also fig.); to seize; to hold; assurance; certainty; sure (of the outcome)
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