Pretty printer for module import dtrace output

pretty_profile.py

!/usr/bin/env python3
#
# Pretty print module import dtrace output.  First column is elapsed time in ms.  Second column is % of total time.
import sys
import fileinput

def main():
    first = None
    lines = []
    for line in fileinput.input():
        if not line.strip():
            break
        ts, _, rest = line.partition('\t')
        ts = int(ts)
        rest = rest.strip()
        if first is None:
            first = ts
            ts = 0
        else:
            ts -= first
        lines.append((ts, rest))
    last = ts
    for ts, line in lines:
        print('%8.3f %6.1f %s' % (float(ts)/1e6, 100*float(ts)/last, line))

if __name__ == '__main__':
    main()