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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 get_arcs(analysis):
 """ Hit stats for each branch. Returns a flat list where every four values represent a branch: 1. line-number 2. block-number (not used) 3. branch-number 4. hits (we only get 1/0 from coverage.py) """

        if not analysis.has_arcs():
            return None

        branch_lines = analysis.branch_lines()
        branches = []

        for l1, l2 in analysis.arcs_executed():
            if l1 in branch_lines:
                branches.extend((l1, 0, abs(l2), 1))

        for l1, l2 in analysis.arcs_missing():
            if l1 in branch_lines:
                branches.extend((l1, 0, abs(l2), 0))

        return branches