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These protobuf messages are equivalent to the Go structs shown earlier.
You’ll notice the two syntaxes are very similar: in Go you have struct, and
with protobuf you have a message—both with a list of fields. In Go you put
the name of the field on the left followed by its type, and with protobuf you
put the name of the field on right followed by its name (with an additional
field ID).

the name of the field on right followed should read “the type of the field on left followed”.