name of file to be parsed. NOTE: if file
was created via stream_tweets, then it will
end in ".json" (see example below)
clean_tweets
logical indicating whether to remove non-ASCII
characters in text of tweets. defaults to TRUE.
as_double
logical indicating whether to handle ID variables
as double (numeric) class. By default, this is set to FALSE, meaning
ID variables are treated as character vectors. Setting this to
TRUE can provide performance (speed and memory) boost but can also
lead to issues when printing and saving, depending on the format.