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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 is_start_of_function(text):

 """Return True if text is the beginning of the function definition."""

    if isinstance(text, str) or isinstance(text, unicode):
        function_prefix = ['def', 'async def']
        text = text.lstrip()

        for prefix in function_prefix:
            if text.startswith(prefix):
                return True

    return False