How to Create a Data Formatter Class in Python

class DataFormatter:
    """Helper class for beginners to format common data types."""
    
    def __init__(self, name="data"):
        self.name = name
        self.records = []
    
    def add_record(self, key, value):
        """Add a key-value record to the formatter."""
        self.records.append({"key": key, "value": value})
        return self
    
    def format_list(self, items, separator=", "):
        """Format a list into a string with a custom separator."""
        return separator.join(str(item) for item in items)
    
    def format_dict(self, data):
        """Format a dictionary as 'key=value' pairs joined by '&'."""
        return "&".join(f"{k}={v}" for k, v in data.items())
    
    def summary(self):
        """Return a readable summary of all added records."""
        lines = [f"{self.name} summary:"]
        for record in self.records:
            lines.append(f"  {record['key']}: {record['value']}")
        return "\n".join(lines)


if __name__ == "__main__":
    formatter = DataFormatter("fruits")
    formatter.add_record("count", 3).add_record("style", "fresh")
    print(formatter.format_list(["apple", "banana", "cherry"]))
    print(formatter.format_dict({"color": "red", "size": "medium"}))
    print(formatter.summary())