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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 pick_input_v1(self):
 """Updates |Input| based on |Total|."""

    flu = self.sequences.fluxes.fastaccess
    inl = self.sequences.inlets.fastaccess
    flu.input = 0.
    for idx in range(inl.len_total):
        flu.input += inl.total[idx][0]