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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 _format_line(headers, fields):
 """Format a line of a table. Arguments: headers: A list of strings that are used as the table headers. fields: A list of the same length as `headers` where `fields[i]` is the entry for `headers[i]` in this row. Elements can be of arbitrary types. Pass `headers` to print the header row. Returns: A pretty string. """

  assert len(fields) == len(headers), (fields, headers)
  fields = ["%2.4f" % field if isinstance(field, float) else str(field)
            for field in fields]
  return '  '.join(' ' * max(0, len(header) - len(field)) + field
                   for (header, field) in zip(headers, fields))