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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def mapping_to_str(mapping):
 """Convert mapping to string"""

    result = ["<"]
    for i, (key, value) in enumerate(mapping.items()):
        if i > 0:
            result.append(",")
        result += [key, "=", serialize_for_header(key, value)]
    result += [">"]
    return "".join(result)