In Python, using PyPDF$2$ and NLTK$.$ You are a data scientist that works in higher education field. You are asked to perform the following tasks on the 'AIED$2021\_$at$\_$risk$\_$pred.pdf$\text{'}$ file.

You are asked to perform the following tasks:

$$ Q$1.$ Extract all texts from the given pdf file.

$$ Q$2.$ Extract all the tokens from the texts.

$$ Q$3.$ Perform Stemming on the texts.

$$ Q$4.$ Perform Lemmatization on the texts.

$$ Q$5.$ Remove all the default stop words in NLTK from the texts.

$$ Q$6.$ Customize the stop words in NLTK by

$+$ Adding "language" and "processing" to the stop words.

$+$ Remove "most" from the default stop words.

Then remove all the customized default stop words from the texts.

$$ Q$7.$ Perform the part of speech tagging for the texts.

$$ Q$8.$ Perform the named entities recognization for the texts.