The exemption in section 13(a)(13) of the Act need not be considered unless the employee is “engaged in commerce or the production of goods for commerce” or is employed in an “enterprise engaged in commerce or in the production of goods for commerce,” as those words are defined in the Act, so as to come within the general scope of sections 6 and 7. The principles of coverage are discussed in part 776 of this chapter and the discussion will not be repeated in this part. Neither does this part discuss the exemptions provided in section 13(a)(6) and 13(b)(12), or section 3(f) which includes in the definition of agriculture forestry or lumbering operations performed by a farmer or on a farm as an incident to or in conjunction with certain farming operations. (See part 780 of this chapter.)