### Install activemodel-csv_validator Gem

Source: https://github.com/aki77/activemodel-csv_validator/blob/master/README.md

Instructions for installing the activemodel-csv_validator gem using Bundler or directly via the gem command. This is the first step to using the validator in your Ruby on Rails application.

```Ruby
gem 'activemodel-csv_validator'
```

--------------------------------

### ActiveModel CSV Validation Example

Source: https://github.com/aki77/activemodel-csv_validator/blob/master/README.md

Demonstrates how to use the activemodel-csv_validator in a Ruby class that includes ActiveModel::Model. It shows how to define a validator for a file attribute, specifying minimum and maximum rows and required headers.

```Ruby
class CsvForm
  include ActiveModel::Model

  attr_accessor :file

  validates :file, presence: true, csv: { min: 1, max: 100, headers: %w[field1 field2 field3] }
end
```

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