Consolidate and clean-up Fetch CSV file interactions

[oree-xx]

Fixes

• Fixes Consolidate and clean-up Fetch CSV file interactions #282

Description

• Cleaned up repeated write_to_sv functions in fetch scripts.
• Added rows_to_csv function to shared.py for appending data to csv file.
• Removed the initialise_data function in arxiv fetch script
• Changed the function name data_to_csv to dataframe_to_csv

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[TimidRobot]

Please update per #217:

        with open(FILE_COUNT, "r", encoding="utf-8") as file_obj:

[TimidRobot]

This PR is looking great!

Please also update gcs_fetch.py to use shared.rows_to_csv() along with changes requested below.

[TimidRobot]

This is inconsistency is not the consequence of your work, but please update per #217:

        with open(FILE_1_METRICS, "r", encoding="utf-8") as file_obj:

[TimidRobot]

This is inconsistency is not the consequence of your work, but please update per #217:

        with open(FILE_1_METRICS, "r", encoding="utf-8") as file_obj:

[TimidRobot]

Please add optional append argument so that fetch scripts like gcs_fetch.py can call it with append=True.

Continue to use mode "w" (open for writing, truncating the file first) by default and then mode "a" (open for writing, appending to the end of file if it exists) when append is True.

See also: open — Built-in Functions — Python 3.11.14 documentation

Also note that writer.writeheader() should be skipped if appending.