In this task, you are given an input list A. You need to find all the elements of the list that are numbers and calculate their sum.
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Question: ['4607', 'T', 'a', '6077', 'c', '4761']

Answer: 15445


Question: ['X', 'u', 'B', '269', '9089', 'M', '5175', 'K']

Answer: 14533


Question: ['T', '5629', 'S', '5837', 'Q', 'P', '4039', 't', 'M', 'H', '863', 'w']

Answer:
16368