cur.execute() psycopg2.ProgrammingError: can't call .execute() on named cursors more than once - postgresql

Question

I'm trying to get this code to run but I get this error above. Can someone please help? I've tried reading about this in other posts but I don't really know how to apply it here. I'm trying to iterate over lines of this database and select 1400 random ones. It blocks on the error above.
def paragraph_generator(test=True, itersize=5000, year=None, state=None):
con, cur = database_connection.connect(cursor_type="server")
cur.itersize = itersize
while True:
sql = f"""
SELECT
text_id,
lccn_sn,
date,
ed,
seq,
chroniclingamerica_meta.statefp,
chroniclingamerica_meta.countyfp,
text_ocr
FROM
chroniclingamerica natural join chroniclingamerica_meta
WHERE date_part('year',date) BETWEEN 1860 AND 1920
ORDER BY RANDOM()
LIMIT 1400
"""
if test:
sql = (
sql + " limit 10000"
) # limit 1000 means it only goes through 1000 lines of the database
else:
pass
print(sql)
cur.execute(sql)
for p in cur.fetchall():
tokens = stem_text(p[-1]) # Stem
# print(tokens)
tokens = (
p[-1]
.translate(str.maketrans("", "", punct))
.replace("\n", " ")
.lower()
.split(" ")
)
tokens_3 = [
a for a in tokens if len(a) == 3 if a in wn_lemmas
] # For 3-letter words, only keep WordNet recognized tokens
tokens = gensim.parsing.preprocessing.remove_short_tokens(
tokens, minsize=4
) # Remove 1-, 2-, and 3-letter words
tokens = tokens + tokens_3 # Add back in 3-letter WordNet-recognized tokens
tokens = gensim.parsing.preprocessing.remove_stopword_tokens(
tokens, stopwords=stop_words
) # Remove stopwords in stopword list above
print("THIS IS THE LENGTH OF TOKENS")
a = len(tokens)
print(a)
if len(tokens) != 0:
ocr_2 = 1 - (
len([a for a in tokens if a in wn_lemmas]) / len(tokens)
) # Generate a measure for proportion of OCR errors in a page
else:
ocr_2 = float("nan")
print("THIS IS OCR")
print(ocr_2)
ocr = ocr_2
if ocr < 0.75 and ~np.isnan(
ocr
): # If the % of OCR in a page is less than 75%, then keep the page and all tokens
tokens = tokens
else:
tokens = [] # Otherwise, give it an empty list (i.e. drop the page)
yield tokens
con.close()
Error:
cur.execute(sql)
psycopg2.ProgrammingError: can't call .execute() on named cursors more than once