diff --git a/Exercises/Python_course_2021_exercises_D_part1.ipynb b/Exercises/Python_course_2021_exercises_D_part1.ipynb
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@@ -0,0 +1,184 @@
+{
+ "nbformat": 4,
+ "nbformat_minor": 0,
+ "metadata": {
+ "colab": {
+ "provenance": []
+ },
+ "kernelspec": {
+ "name": "python3",
+ "display_name": "Python 3"
+ }
+ },
+ "cells": [
+ {
+ "cell_type": "markdown",
+ "metadata": {
+ "id": "xqfYLmi0LWEl"
+ },
+ "source": [
+ "# Python course 2023 - Exercises D"
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {
+ "id": "LRZcpmP8LaR_"
+ },
+ "source": [
+ "## Part1 - writing files"
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {
+ "id": "NDIaKYRcLfz1"
+ },
+ "source": [
+ "\n",
+ "\n",
+ "---\n",
+ "1.1) Read the file AtCol0_Exons.fasta and write all headers (starting with '>') into a new file!\n",
+ "\n"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "metadata": {
+ "id": "aO4lTjReLsDC"
+ },
+ "source": [],
+ "execution_count": null,
+ "outputs": []
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {
+ "id": "ddWzYDHlLsMN"
+ },
+ "source": [
+ "\n",
+ "\n",
+ "---\n",
+ "1.2) Read the file AtCol0_Exons.fasta and write the following:\n",
+ "* Line if it is a header\n",
+ "* Length of line if it is a sequence line\n"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "metadata": {
+ "id": "HAaoquFmL4jV"
+ },
+ "source": [],
+ "execution_count": null,
+ "outputs": []
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {
+ "id": "yvanoP6kL4rn"
+ },
+ "source": [
+ "\n",
+ "\n",
+ "---\n",
+ "1.3) Calculate the number of sequences, the cumulative length and the average length in a new file! Are they matching the values of the original file?\n"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "metadata": {
+ "id": "N5lQi7dyMEXf"
+ },
+ "source": [],
+ "execution_count": null,
+ "outputs": []
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {
+ "id": "L4KLtwRJMEgM"
+ },
+ "source": [
+ "\n",
+ "\n",
+ "---\n",
+ "1.4) Write sequences into a new file if their length is a multiple of 10!\n"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "metadata": {
+ "id": "_87Mx4EUMKw9"
+ },
+ "source": [],
+ "execution_count": null,
+ "outputs": []
+ },
+ {
+ "cell_type": "markdown",
+ "source": [
+ "---\n",
+ "#Bonus tasks"
+ ],
+ "metadata": {
+ "id": "4o6oA4DP7uwk"
+ }
+ },
+ {
+ "cell_type": "markdown",
+ "source": [
+ ""
+ ],
+ "metadata": {
+ "id": "_6LzcB_k7st0"
+ }
+ },
+ {
+ "cell_type": "code",
+ "source": [],
+ "metadata": {
+ "id": "PFLIHF017uDk"
+ },
+ "execution_count": null,
+ "outputs": []
+ },
+ {
+ "cell_type": "markdown",
+ "source": [
+ ""
+ ],
+ "metadata": {
+ "id": "EZ4-T_6N-8cT"
+ }
+ },
+ {
+ "cell_type": "code",
+ "source": [],
+ "metadata": {
+ "id": "t8CVqUIh-8kK"
+ },
+ "execution_count": null,
+ "outputs": []
+ },
+ {
+ "cell_type": "markdown",
+ "source": [
+ ""
+ ],
+ "metadata": {
+ "id": "KWBePnj6_AkU"
+ }
+ },
+ {
+ "cell_type": "code",
+ "source": [],
+ "metadata": {
+ "id": "_0AujN32_ArL"
+ },
+ "execution_count": null,
+ "outputs": []
+ }
+ ]
+}
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