lazy_2_1.py

# create a RDD of the text file with Number of Partitions = 4
my_text_file = sc.textFile('tokens_spark.txt',minPartitions=4)

# RDD Object
print(my_text_file)

# convert to lower case
my_text_file = my_text_file.map(lambda x : x.lower())

# Updated RDD Object
print(my_text_file)

# Get the RDD Lineage
print(my_text_file.toDebugString())

Really Nice. Please what is the content of your 'tokens_spark.txt' file?
Thanks in advance.

I used the below to create a file just for those who may need it:

with open('spark_tokens.txt', 'w') as outfile:
    words = ['Python', 'Java', 'Scala', 'Others', 'Spark', 'APACHE', 'Cool', 'udpate', 'Good_to_GO']
    for i in range(100000): outfile.write(words[randint(0, len(words)-1)] + '\n')