Learning actual functions and syntax used for opening files and not relying on helper functions

Course Q&A AI Python for Beginners
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1

In Module 3: lesson 2, we are relying on the helper functions for opening and reading files in python. I’m going through the helper function.py file to understand how I would do this without relying on the helper functions and it appears there are long-winded functions for doing so. Do these need to be defined everytime we write our own code requiring external files or is there a library that contains functions that can look after these for us?

I’m assuming the libraries we require to open and read files are:

  • import io
  • import csv

Here are the code blocks for opening and reading files:

def read_csv_dict(csv_file_path):
“”“This function takes a csv file and loads it as a dict.”“”
# Initialize an empty list to store the data
data_list = []

# Open the CSV file
with open(csv_file_path, mode='r') as file:
    # Create a CSV reader object
    csv_reader = csv.DictReader(file)

    # Iterate over each row in the CSV file
    for row in csv_reader:
        # Append the row to the data list
        data_list.append(row)

# Convert the list to a dictionary
data_dict = {i: data_list[i] for i in range(len(data_list))}
return data_dict


def upload_txt_file():
    """
    Uploads a text file and saves it to the specified directory.
    
    Args:
        directory (str): The directory where the uploaded file will be saved. 
        Defaults to the current working directory.
    """
    # Create the file upload widget
    upload_widget = widgets.FileUpload(
        accept='.txt',  # Accept text files only
        multiple=False  # Do not allow multiple uploads
    )
    # Impose file size limit
    output = widgets.Output()
    
    # Function to handle file upload
    def handle_upload(change):
        with output:
            output.clear_output()
            # Read the file content
            content = upload_widget.value[0]['content']
            name = upload_widget.value[0]['name']
            size_in_kb = len(content) / 1024
            
            if size_in_kb > 3:
                print(f"Your file is too large, please upload a file that doesn't exceed 3KB.")
                return
		    
            # Save the file to the specified directory
            with open(name, 'wb') as f:
                f.write(content)
            # Confirm the file has been saved
            print(f"The {name} file has been uploaded.")

    # Attach the file upload event to the handler function
    upload_widget.observe(handle_upload, names='value')

    display(upload_widget, output)
2

If they are as libraries or written by you in separate files, then you can just import them, no need to write them all over again when you build a new program!