input: from typing import List
  
  def search_customer_data(customer_data: List[str], name: str) -> str:
      """
      Searches for customer data by customer name in a given list of customer data.
      Returns the first matching customer entry.
      
      >>> search_customer_data(["John Doe", "Jane Smith", "John Smith"], "Jane")
      "Jane Smith"
      >>> search_customer_data(["John Doe", "Jane Smith", "John Smith"], "John")
      "John Doe"
      >>> search_customer_data(["John Doe", "Jane Smith", "John Smith"], "Mary")
      ""
      """
      for customer in customer_data:
          if name.lower() in customer.lower():
              return customer
      return ""
output:     for customer in customer_data:
          if name.lower() in customer.lower():
              return customer
      return ""