Python faker - Syntax error - CSV file

Question

Python Syntax Error - CSV file input: I'm trying to use CSV masking test for an implementation and picked up use case from masking using faker. Picked up the sample code from the link and trying to execute the program. But I'm getting syntax error when accessing the csv file.

import unicodecsv as csv
from faker import Factory
from collections import defaultdict



def anonymize_rows(rows):
"""
Rows is an iterable of dictionaries that contain name and
email fields that need to be anonymized.
"""
# Load the faker and its providers
faker  = Factory.create()

# Create mappings of names & emails to faked names & emails.
names  = defaultdict(faker.name)
emails = defaultdict(faker.email)

# Iterate over the rows and yield anonymized rows.
for row in rows:
    # Replace the name and email fields with faked fields.
    row['name']  = names[row['name']]
    row['email'] = emails[row['email']]

    # Yield the row back to the caller
    yield row


   def anonymize('masktest.csv', 'masktest_tgt.csv'):
"""
The source argument is a path to a CSV file containing data to anonymize,
while target is a path to write the anonymized CSV data to.
"""
with open('masktest.csv', 'rU') as f:
     with open('masktest_tgt.csv', 'w') as o:
        # Use the DictReader to easily extract fields
        reader = csv.DictReader(f)
        writer = csv.DictWriter(o, reader.fieldnames)

        # Read and anonymize data, writing to target file.
        for row in anonymize_rows(reader):
            print (row['name'])
            writer.writerow(row)

 

Traceback (most recent call last):
  File "python", line 34
    def anonymize('masktest.csv', 'masktest_tgt.csv'):
                               ^
SyntaxError: invalid syntax

Answer 1

Word def is used only for defining function.

To call a function use its name and parameters without "def":

faked_values = anonimize('file.csv', 'file2.csv')

Answer 2

If you look at the original definition, you'll see the correct syntax.

def anonymize(source, target):
    """
    The source argument is a path to a CSV file containing data to anonymize,
    while target is a path to write the anonymized CSV data to.
    """
    # more code...

What's different here, is that when you define a function, you must provide valid identifiers in parentheses. An identifier is essentially a name for the variable, what you'll use to refer to the argument inside your function.

Possibly, you meant to do one of the following things:

• Call a function, not define it. In that case, you shouldn't use the def keyword. A call looks like this: func(arg1, arg2). The amount of values in parentheses should generally match up with the amount of identifiers in the function definition. And here, in place of arg1 and arg2, you can use strings or any other literal values or variables that you've defined.

• Make function arguments optional. In this case, the string literals in parentheses should be preceded with an identifier and a = sign, like so: def anonymize(arg1 = 'one', arg2 = 'two'). This will allow you to call a function without a neccesity to provide all arguments. If an argument is not given a value, it will be assigned with a default one that you wrote in the definition. Valid calls will be: anonymize('me'), anonymize(), anonymize(arg2 = 'you'), etc.

Answer 3

Thanks folks. I have removed the function and just passed the input csv file name as a input and it worked like a charm. Here is the code.

import csv
import unicodecsv as csv
from faker import Factory
from collections import defaultdict

def anonymize_rows(rows):
"""
Rows is an iterable of dictionaries that contain name and
email fields that need to be anonymized.
"""
# Load the faker and its providers
faker  = Factory.create()

# Create mappings of names & emails to faked names & emails.
names  = defaultdict(faker.name)
emails = defaultdict(faker.email)

# Iterate over the rows and yield anonymized rows.
for row in rows:
    # Replace the name and email fields with faked fields.
    row['name']  = names[row['name']]
    row['email'] = emails[row['email']]

    # Yield the row back to the caller
    yield row

#def anonymize('masktest.csv', 'masktest_tgt.csv'):
"""
The source argument is a path to a CSV file containing data to anonymize,
while target is a path to write the anonymized CSV data to.
"""
with open('masktest.csv', 'rU') as f:
with open('masktest_tgt.csv', 'w') as o:
        # Use the DictReader to easily extract fields
    reader = csv.DictReader(f)
    writer = csv.DictWriter(o, reader.fieldnames)

        # Read and anonymize data, writing to target file.
    for row in anonymize_rows(reader):
        print (row['name'])
        writer.writerow(row)

Input: id,name,email,phone 123,dave jackson,dave.jackson@email.com,212-121-3234

masked output: 123,Elizabeth Myers MD,alicia70@hotmail.com,212-121-3234