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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 _serialize_fields(point):
 """Field values can be floats, integers, strings, or Booleans."""

    output = []
    for k, v in point['fields'].items():
        k = escape(k, key_escape)
        if isinstance(v, bool):
            output.append(f'{k}={v}')
        elif isinstance(v, int):
            output.append(f'{k}={v}i')
        elif isinstance(v, str):
            output.append(f'{k}="{v.translate(str_escape)}"')
        elif v is None:
            # Empty values
            continue
        else:
            # Floats
            output.append(f'{k}={v}')
    return ','.join(output)