Recommend movies based on the ratings:
Sort by User IDs
number of unique users in the dataset
number of unique movies in the dataset
converting long data into wide data using pivot
Replacing the index values by unique user Ids
Impute those NaNs with 0 values
Calculating Cosine Similarity between Users on array data
Store the results in a dataframe format
Set the index and column names to user ids
Slicing first 5 rows and first 5 columns
Nullifying diagonal values
Most Similar Users
extract the movies which userId 6 & 168 have watched