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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 write(name, value):
 """Write a raw env value. A ``None`` value clears the environment variable. Args: name: The environment variable name value: The value to write """

    if value is not None:
        environ[name] = builtins.str(value)
    elif environ.get(name):
        del environ[name]