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    "List comprehension\n",
    "------------------\n",
    "\n",
    "Python offers a compact method called \"list comprehension\" to create lists from lists.\n",
    "Consider the following case of a list that is processed to create another list:"
   ]
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    "iterable=range(5)\n",
    "my_list=[]\n",
    "\n",
    "for x in iterable:\n",
    "    if x<=3:\n",
    "        my_list.append(x**2)\n",
    "\n",
    "print (my_list)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Using list comprehension this can be done using the following line:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "my_list=[x**2 for x in iterable if x<=3]\n",
    "\n",
    "print (my_list)"
   ]
  },
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   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "You can see that a loop such as\n",
    "\n",
    "    for item in iterable:\n",
    "        if conditional:\n",
    "            expression\n",
    "\n",
    "is equivalent to\n",
    "\n",
    "    [expression for item in iterable if conditional]\n",
    "    \n",
    "    \n",
    "You are always creating a list with list comprehension. If you don't necessarily want a list, a loop can be the simpler option.\n"
   ]
  },
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   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Exercise 1:\n",
    "-----------\n",
    "\n",
    "Use list comprehension to translate the sentence list\n",
    "\n",
    "    diogenes=['Cede','paulum','e','sole']\n",
    "\n",
    "using the dictionary\n",
    "\n",
    "    dic={'Cede':'Go','paulum':'a little','e':'out of','sole':'the sun'}\n",
    "    \n",
    "into an answer sentence list.     "
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "# your solution here"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Exercise 2:\n",
    "-----------\n",
    "\n",
    "Use list comprehension to determine a list with all numbers between 1 and 1000 for which the digit sum is equal to 7."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "# your solution here"
   ]
  }
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