实现链路追踪TraceID传播

def solve():
    from pyodide.http import open_url
    from io import StringIO
    traffic_log_csv = open_url(____).read()
    import uuid
    class TraceContext:
        def __init__(____):
            self.trace_id = trace_id or uuid.uuid4().hex[:____]
            self.span_id = uuid.uuid4().hex[:____]
            self.parent_span_id = parent_span_id
        def child(____):
            return TraceContext(____)
        def to_headers(____):
            h = {'____': self.trace_id, '____': self.span_id}
            if self.parent_span_id: h['____'] = self.parent_span_id
            return h
    root = TraceContext()
    svc_calls = ['____','____','____']
    spans = [root]
    for svc in svc_calls:
        child = root.child()
        spans.append(____)
        print(____)
    print(____)
    print(____)