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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_definition_section(source):
 """Determine if the source is a definition section. Args: source: The usage string source that may be a section. Returns: True if the source describes a definition section; otherwise, False. """

    try:
        definitions = textwrap.dedent(source).split('\n', 1)[1].splitlines()
        return all(
            re.match(r'\s\s+((?!\s\s).+)\s\s+.+', s) for s in definitions)
    except IndexError:
        return False