notebooks/answers/5 - Modules.ipynb

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   "source": [
    "# Modules"
   ]
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   "source": [
    "## import\n",
    "Let's start by using a module. \n",
    "\n",
    "There is a module called `sample_module` in the same directory as this notebook. Inside it there is a function called `sample_function`.\n",
    "\n",
    "Import the function and call it to see what happens. Can you do the import in two different ways?"
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      "Nobody expects the Spanish inquisition!\n"
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    "import sys\n",
    "sys.path.append('../exercises')\n",
    "import sample_module\n",
    "sample_module.sample_function()"
   ]
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    "## import as\n",
    "\n",
    "It is possible to rename the function you are importing by using the syntax\n",
    "\n",
    "```from module import function_name as another_function_name\n",
    "```\n",
    "\n",
    "Go ahead and import `sample_function` using a more descriptive name and call it."
   ]
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      "Nobody expects the Spanish inquisition!\n"
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   "source": [
    "from sample_module import sample_function as samp_func\n",
    "samp_func()"
   ]
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   "source": [
    "## Creating a module\n",
    "\n",
    "Now create a module called mymodule (i.e. mymodule.py) using the text editor functionality of Jupyter Notebooks.\n",
    "\n",
    "Add the following code to the module.\n",
    "\n",
    "```\n",
    "def add(a, b):\n",
    "    return a + b\n",
    "```\n",
    "\n",
    "Save the file and import your newly created module in the cell below.\n",
    "\n",
    "If you want you can also use a more inventive name than mymodule.py."
   ]
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    "## Extra: reloading the module\n",
    "\n",
    "Add a new function ``subtract`` to your above module and try to import it again. Are you able to use the ``subtract`` function?"
   ]
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    "Python keeps track of modules that are imported, and performs the actual import only with the first ``import mymodule`` statement. If a module is modified during an interactive session, module needs to be explicitly reloaded in order to changes take effect. Reloading can be done with the function ``reload`` in the built-in module ``importlib``:"
   ]
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  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {
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   "outputs": [],
   "source": [
    "from importlib import reload\n",
    "reload(mymodule)"
   ]
  }
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