Advanced Code Example — Variables, Expressions & Data Types#

This example extends the basic module code into a more complete customer analytics workflow. It demonstrates type inspection, formatted output, boolean logic, and derived calculations — all using only variables, expressions, and data types.

Business Scenario#

You are an analyst at a regional retail chain. Given a customer’s transaction history, you need to:

Store and organize customer data using appropriate data types
Calculate key metrics: total spend, average purchase, and spend category
Format the results for a business-readable report
Apply boolean logic to determine eligibility flags

Code#

# ── Customer Profile ────────────────────────────────────────────────
customer_name: str = 'Alice Johnson'
customer_id: int = 1001
customer_region: str = 'Northwest'
is_loyalty_member: bool = True

# ── Transaction Data (individual floats) ────────────────────────────
purchase_jan: float = 250.50
purchase_feb: float = 180.75
purchase_mar: float = 420.25
purchase_apr: float = 315.00

# ── Derived Metrics ─────────────────────────────────────────────────
total_spent: float = purchase_jan + purchase_feb + purchase_mar + purchase_apr
num_purchases: int = 4
average_purchase: float = total_spent / num_purchases

# ── Business Rules via Boolean Expressions ──────────────────────────
qualifies_for_gold: bool = total_spent >= 500
qualifies_for_platinum: bool = total_spent >= 1000 and num_purchases >= 4
qualifies_for_free_shipping: bool = is_loyalty_member and total_spent > 300

# ── Tier Assignment using Conditional Expression ────────────────────
customer_tier: str = (
    'Platinum' if qualifies_for_platinum
    else 'Gold' if qualifies_for_gold
    else 'Standard'
)

# ── String Formatting for Report Output ─────────────────────────────
separator: str = '-' * 45

print(separator)
print(f"  CUSTOMER ANALYTICS REPORT")
print(separator)
print(f"  Name     : {customer_name}")
print(f"  ID       : {customer_id}")
print(f"  Region   : {customer_region}")
print(f"  Member   : {'Yes' if is_loyalty_member else 'No'}")
print(separator)
print(f"  Total Spent     : ${total_spent:,.2f}")
print(f"  Avg Purchase    : ${average_purchase:,.2f}")
print(f"  Num Purchases   : {num_purchases}")
print(separator)
print(f"  Tier            : {customer_tier}")
print(f"  Free Shipping   : {'Yes' if qualifies_for_free_shipping else 'No'}")
print(separator)

# ── Data Type Inspection ─────────────────────────────────────────────
print("\n  DATA TYPE SUMMARY:")
print(f"  customer_name    -> {type(customer_name).__name__}")
print(f"  customer_id      -> {type(customer_id).__name__}")
print(f"  total_spent      -> {type(total_spent).__name__}")
print(f"  is_loyalty_member-> {type(is_loyalty_member).__name__}")
print(f"  customer_tier    -> {type(customer_tier).__name__}")

Expected Output#

---------------------------------------------
  CUSTOMER ANALYTICS REPORT
---------------------------------------------
  Name     : Alice Johnson
  ID       : 1001
  Region   : Northwest
  Member   : Yes
---------------------------------------------
  Total Spent     : $1,166.50
  Avg Purchase    : $291.63
  Num Purchases   : 4
---------------------------------------------
  Tier            : Platinum
  Free Shipping   : Yes
---------------------------------------------

  DATA TYPE SUMMARY:
  customer_name    -> str
  customer_id      -> int
  total_spent      -> float
  is_loyalty_member-> bool
  customer_tier    -> str

Key Concepts Demonstrated#

Concept	Where in Code
Type annotations	`customer_name: str = 'Alice Johnson'`
Float arithmetic	`total_spent / num_purchases`
Compound boolean	`total_spent >= 1000 and num_purchases >= 4`
Conditional expression	`'Platinum' if ... else 'Gold' if ... else 'Standard'`
f-string formatting	`f"${total_spent:,.2f}"`
Type inspection	`type(customer_name).__name__`

What to Notice#

Type annotations (the : str, : float hints) don’t change how Python works — they’re documentation that makes code more readable and understandable for colleagues and tools.

The conditional expression on the tier assignment is a compact way to assign a value based on conditions. It reads like natural language: “Platinum if platinum conditions are met, else Gold if gold conditions, else Standard.”

f-string formatting with {total_spent:,.2f} applies two formatting rules: , adds thousands separators and .2f rounds to 2 decimal places — essential for any currency display in business reporting.

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