What should be included in a Lettre de motivation?

[Caespar]

Hi there,

I am writing on an application to a M2 course (master's course/programme) and I need to write a lettre de motvation. I guess I should write what I expect to gain from this one year long programme and why I applied to this particular university. But do French universities expect us to write anything else such as "who I am", what particular subfield (in the subject I am reading/applying to) intrigues me, future plans and so on?

Thank you.