Class _Printer

Initialize the Printer.

Double values can be formatted compactly with 15 digits of precision
(which is the most that IEEE 754 "double" can guarantee) using
double_format='.15g'. To ensure that converting to text and back to a proto
will result in an identical value, double_format='.17g' should be used.

Args:
  out: To record the text format result.
  indent: The initial indent level for pretty print.
  as_utf8: Return unescaped Unicode for non-ASCII characters.
      In Python 3 actual Unicode characters may appear as is in strings.
      In Python 2 the return value will be valid UTF-8 rather than ASCII.
  as_one_line: Don't introduce newlines between fields.
  use_short_repeated_primitives: Use short repeated format for primitives.
  pointy_brackets: If True, use angle brackets instead of curly braces for
    nesting.
  use_index_order: If True, print fields of a proto message using the order
    defined in source code instead of the field number. By default, use the
    field number order.
  float_format: If set, use this to specify float field formatting
    (per the "Format Specification Mini-Language"); otherwise, 8 valid
    digits is used (default '.8g'). Also affect double field if
    double_format is not set but float_format is set.
  double_format: If set, use this to specify double field formatting
    (per the "Format Specification Mini-Language"); if it is not set but
    float_format is set, use float_format. Otherwise, str() is used.
  use_field_number: If True, print field numbers instead of names.
  descriptor_pool: A DescriptorPool used to resolve Any types.
  message_formatter: A function(message, indent, as_one_line): unicode|None
    to custom format selected sub-messages (usually based on message type).
    Use to pretty print parts of the protobuf for easier diffing.
  print_unknown_fields: If True, unknown fields will be printed.

Overrides: object.__init__

Convert protobuf message to text format.

Args:
  message: The protocol buffers message.

Print a single field value (not including name).

For repeated fields, the value should be a single element.

Args:
  field: The descriptor of the field to be printed.
  value: The value of the field.