Returns audit entries stored in the database.

def ReadAPIAuditEntries(self,
                          username=None,
                          router_method_names=None,
                          min_timestamp=None,
                          max_timestamp=None):
    """Returns audit entries stored in the database."""
    results = []

    for entry in self.api_audit_entries:
      if username is not None and entry.username != username:
        continue

      if (router_method_names and
          entry.router_method_name not in router_method_names):
        continue

      if min_timestamp is not None and entry.timestamp < min_timestamp:
        continue

      if max_timestamp is not None and entry.timestamp > max_timestamp:
        continue

      results.append(entry)

    return sorted(results, key=lambda entry: entry.timestamp)