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Optional. Represents the name of an extended deployment property. Each
extended property must have a defined name and a value. You can have a
maximum of 25 extended property name/value pairs. The maximum length of
the name element is 64 characters, only alphanumeric characters and
underscores are valid in the name, and the name must start with a
letter. Attempting to use other characters, starting the name with a
non-letter character, or entering a name that is identical to that of
another extended property owned by the same hosted service will result
in a status code 400 (Bad Request) error.