Exercise: Read CSV File

Sample CSV File

The following table (download CSV) is an excerpt from a stock exchange procedure [1]. In its visual form, it would be nicely made up, headed by a row that contains the column names.

FUND_NAME	FUND_ISIN	FUND_TICKER	AS_OF_DATE	FUND_IN_UNIVERSE	FUND_OF_FUNDS	FUND_HOLDINGS_COUNT	FUND_HOLDING_FUNDS_COUNT
American Funds American Balanced Fund;A	US0240711020	ABALX	20210103	T		2,084	0
Dodge & Cox Balanced Fund	US2562011047	DODBX	20210103	T	T	410	1
Dodge & Cox Stock Fund	US2562191062	DODGX	20210103	T	T	74	1
Franklin Income Fund;A1	US3534963000	FKINX	20210103	T	T	302	1
American Funds Growth Fund of America;A	US3998741066	AGTHX	20210103	T		378	0
T Rowe Price Growth Stock Fund	US7414791092	PRGFX	20210103	T	T	87	1
Fidelity Puritan Fund	US3163451079	FPURX	20210103	T		1,124	0
Fidelity Contrafund	US3160711095	FCNTX	20210103	T		363	0
T Rowe Price Capital Appreciation Fund	US77954M1053	PRWCX	20210103	T	T	165	2
Old Westbury Large Cap Strategies Fund	US6804141090	OWLSX	20210103	T	T	199	2
American Funds Capital Income Builder;A	US1401931035	CAIBX	20210103	T		1,582	0
Harbor Capital Appreciation Fund;Institutional	US4115115044	HACAX	20210103	T		55	0
T Rowe Price Blue Chip Growth Fund	US77954Q1067	TRBCX	20210103	T	T	123	1
Dreyfus Treasury Securities Cash Management;Inst	US2619411083	DIRXX	20210103	T		50	0
BlackRock Global Allocation Fund;Institutional	US09251T5092	MALOX	20210103	T	T	1,241	16
Fidelity Low-Priced Stock Fund	US3163453059	FLPSX	20210103	T		799	0
BlackRock Liquidity Treasury Trust Fund;Inst	US09248U5517	TTTXX	20210103	T		63	0
DFA Five-Year Global Fixed Income Portfolio;Inst	US2332038841	DFGBX	20210103	T		350	0
Federated Hermes US Treasury Cash Reserves;Inst	US60934N6821	UTIXX	20210103	T		55	0
Oakmark International Fund;Investor	US4138382027	OAKIX	20210103	T		80	0
Advanced Srs T Rowe Price Asset Allocation Port	US00767H4939		20210103	T		2,787	0
FPA Crescent Fund;Inst	US30254T7596	FPACX	20210103	T		138	0
Franklin Income Fund;C	US3534968058	FCISX	20210103	T	T	302	1
MFS Value Fund;I	US5529836943	MEIIX	20210103	T		76	0
Goldman Sachs FS Treasury Instruments Fd;Inst	US38142B5003	FTIXX	20210103	T		67	0
Schwab S&P 500 Index Fund	US8085098551	SWPPX	20210103	T		508	0
Templeton Global Bond Fund;Advisor	US8802084009	TGBAX	20210103	T	T	82	1
First Eagle Global Fund;I	US32008F6060	SGIIX	20210103	T	T	225	1
iShares Core S&P 500 ETF	US4642872000	IVV	20210103	T	T	507	1
Vanguard 500 Index Fund;Admiral	US9229087104	VFIAX	20210103	T		510	0
Vanguard Total Stock Market Index Fund;Admiral	US9229087286	VTSAX	20210103	T		3,370	0
SPDR S&P MidCap 400 ETF	US78467Y1073	MDY	20210103	T		400	0
SPDR Dow Jones Industrial Average ETF Trust	US78467X1090	DIA	20210103	T		31	0
Health Care Select Sector SPDR Fund	US81369Y2090	XLV	20210103	T	T	64	1
Consumer Discretionary Select Sector SPDR Fund	US81369Y4070	XLY	20210103	T	T	62	1
Energy Select Sector SPDR Fund	US81369Y5069	XLE	20210103	T	T	28	1
Financial Select Sector SPDR Fund	US81369Y6059	XLF	20210103	T	T	66	1
Technology Select Sector SPDR Fund	US81369Y8030	XLK	20210103	T	T	74	1
Invesco QQQ Trust Series 1	US46090E1038	QQQ	20210103	T		104	0
Dodge & Cox International Stock Fund	US2562061034	DODFX	20210103	T	T	80	1
iShares MSCI EAFE ETF	US4642874659	EFA	20210103	T	T	897	1
JPMorgan 100% US Treasury Secs Mny Mkt Fd;Inst	US4812A28358	JTSXX	20210103	T		41	0
Invesco S&P 500 Eql Wght ETF	US46137V3574	RSP	20210103	T	T	507	1
JPMorgan 100% US Treasury Secs Mny Mkt Fd;Capital	US4812A03757	CJTXX	20210103	T		41	0
Invesco Developing Markets Fund;Y	US00143W8753	ODVYX	20210103	T	T	72	3
SPDR S&P Dividend ETF	US78464A7634	SDY	20210103	T	T	118	1
DFA International Core Equity Portfolio;Inst	US2332033719	DFIEX	20210103	T		4,888	0
Edgewood Growth Fund;Institutional	US0075W07594	EGFIX	20210103	T	T	23	1
Advanced Series Prudential Growth Allocation Port	US00767H7585		20210103	T	T	2,400	3
MFS Value Fund;R6	US55273H3536	MEIKX	20210103	T		76	0

Requirement

1. Write a function read_stock() that …

   • takes a filename parameter

   • reads the CSV (using a csv.DictReader to automatically absorb the header line of the CSV file into dictionary keys), and thereby converts the fields as follows,

     • FUND_NAME: str

     • FUND_ISIN: str

     • FUND_TICKER: str

     • AS_OF_DATE: datetime

     • FUND_IN_UNIVERSE: bool (interpreting T and F straightforwardly)

     • FUND_HOLDINGS_COUNT: float

     • FUND_HOLDING_FUNDS_COUNT: float

   • returns a list of dictionaries (better yet: an iterable).

2. Put that function in a module, say stock.py

3. Write an executable program, say read-stock.py, that is called like follows,

   $ python read-stock.py stock.csv
   ...
   

   It then writes the returned dictionaries/record to stdout in the most beautiful way you can come up with.

Footnotes

[1]

Although I make a living from what I do, I hardly know what money is. Lets take the CSV as a representative example, and not try to understand what’s in it.

Dependencies