Represents file metadata.
Create a file from a map.
@type t() :: %MistralClient.Models.File{ bytes: integer(), created_at: integer(), filename: String.t(), id: String.t(), num_lines: integer() | nil, object: String.t(), purpose: String.t(), sample_type: String.t() | nil, source: String.t() | nil }
@spec from_map(map()) :: t()