code: def crypto_core_ed25519_is_valid_point(p):
      
      ensure(isinstance(p, bytes) and len(p) == crypto_core_ed25519_BYTES,
             'Point must be a crypto_core_ed25519_BYTES long bytes sequence',
             raising=exc.TypeError)
  
      rc = lib.crypto_core_ed25519_is_valid_point(p)
      return rc == 1
docs: Check if ``p`` represents a point on the edwards25519 curve, in canonical
      form, on the main subgroup, and that the point doesn't have a small order.
  
      :param p: a :py:data:`.crypto_core_ed25519_BYTES` long bytes sequence
                representing a point on the edwards25519 curve
      :type p: bytes
      :return: point validity
      :rtype: bool