def acquire_page_list_urls_books(soup):
	"""
	Take a BeautifulSoup content of a category page.
	Return a list of the urls of the books 
	in the first page for a unique category.
	"""
	page_list_partial_urls_books = map(
		lambda x: x.a['href'][8:],
		soup.find_all('h3'),
	)
	page_list_urls_books = map(
		lambda x: f"http://books.toscrape.com/catalogue{x}",
		page_list_partial_urls_books,
	)
	return list(page_list_urls_books)