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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_bridges(vnic_dir='/sys/devices/virtual/net'):
 """Return a list of bridges on the system."""

    b_regex = "%s/*/bridge" % vnic_dir
    return [x.replace(vnic_dir, '').split('/')[1] for x in glob.glob(b_regex)]