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'''** DO NOT USE - TO BE UPDATED FOR CENTOS 8.0 **'''
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= LAB OBJECTIVES =
<blockquote style="margin-left:35px;">{{Admon/caution|style="padding-left:25px"|Risk of Losing File Contents|A common problem that new Python programmers may encounter is to accidentally erase existing contents of a file when writing new data to a file. When opening files for writing (using the ''''w'''' open function option), Python assumes existing content in the file is no longer wanted and it's immediately deleted; therefore, if you wish to write data to a file but keep existing content, you need to use the open file option ''''a'''' (append new data to a file).}}</blockquote>
:#When opening a file for writing, the ''''w'''' option is specified with the '''open()''' function. When the 'w' option is specified - previous (existing) content inside the file is deleted. This deletion takes place the moment the open() function is executed, not when writing to the file. If the file that is being written to doesn't exist, the file will be created upon the file opening process.<br><br>
:#Create a temporary Python file and open a non-existent data file (called file1.txt) for writing:<source lang="python">
f = open('file1.txt', 'w')
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= INVESTIGATION 2: Exceptions and Error Handling =
:Running into errors in programming will be a common occurrence. You should expect that it will happen for any code that you write. In python , when an error occurs, the python runtime raises an '''exception'''. This section will teach you to catch these exceptions when they happen and to allow the program to continue running, or to stop program execution with a readable error message.
== PART 1 - Handling Errors ==
