Loading a pickled file
There are a number of datatypes that cannot be saved easily to flat files, such as lists and dictionaries. If you want your files to be human readable, you may want to save them as text files in a clever manner. JSONs, which you will see in a later chapter, are appropriate for Python dictionaries.
However, if you merely want to be able to import them into Python, you can serialize them. All this means is converting the object into a sequence of bytes, or a bytestream.
In this exercise, you'll import the pickle
package, open a previously
pickled data structure from a file and load it.
This exercise is part of the course
Introduction to Importing Data in Python
Exercise instructions
- Import the
pickle
package. - Complete the second argument of
open()
so that it is read only for a binary file. This argument will be a string of two letters, one signifying 'read only', the other 'binary'. - Pass the correct argument to
pickle.load()
; it should use the variable that is bound toopen
. - Print the data,
d
. - Print the datatype of
d
; take your mind back to your previous use of the functiontype()
.
Hands-on interactive exercise
Have a go at this exercise by completing this sample code.
# Import pickle package
# Open pickle file and load data: d
with open('data.pkl', ____) as file:
d = pickle.load(____)
# Print d
print(____)
# Print datatype of d
print(____)