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Python control flow patterns

Python control flow patterns allow developers to implement logic and rules within their code, dictating the execution path based on specific conditions^[400-devops-09-scripting-language-python-introduction-readme.md]. The primary mechanism for this is the if, elif, and else structure^[400-devops-09-scripting-language-python-introduction-readme.md].

Conditional Statements

Control flows are used to apply rules such that "if this is the case, then do that, else do something else"^[400-devops-09-scripting-language-python-introduction-readme.md]. This enables functions to perform different actions or return specific data depending on the inputs provided^[400-devops-09-scripting-language-python-introduction-readme.md].

Example Pattern

A common pattern involves validating an input, such as a customerID, against multiple expected values^[400-devops-09-scripting-language-python-introduction-readme.md].

def getCustomer(customerID):
  if customerID == "abc":
    return "Marcel Dempers"
  elif customerID == "def":
    return "Bob Smith"
  else:
    return ""

In this example, the function checks the input sequentially^[400-devops-09-scripting-language-python-introduction-readme.md]: * If customerID matches "abc", it returns the specific name associated with that ID^[400-devops-09-scripting-language-python-introduction-readme.md]. * If that condition is not met, it checks the elif condition for "def"^[400-devops-09-scripting-language-python-introduction-readme.md]. * If no conditions are met, the else block executes, returning an empty string^[400-devops-09-scripting-language-python-introduction-readme.md].

Sources

^[400-devops-09-scripting-language-python-introduction-readme.md]