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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 _parse_docstring(fh):
 """Parse the docstrings of a script to find marked dependencies."""

    find_fades = re.compile(r'\b(fades)\b:').search

    for line in fh:
        if line.startswith("'"):
            quote = "'"
            break
        if line.startswith('"'):
            quote = '"'
            break
    else:
        return {}

    if line[1] == quote:
        # comment start with triple quotes
        endquote = quote * 3
    else:
        endquote = quote

    if endquote in line[len(endquote):]:
        docstring_lines = [line[:line.index(endquote)]]
    else:
        docstring_lines = [line]
        for line in fh:
            if endquote in line:
                docstring_lines.append(line[:line.index(endquote)])
                break
            docstring_lines.append(line)

    docstring_lines = iter(docstring_lines)
    for doc_line in docstring_lines:
        if find_fades(doc_line):
            break
    else:
        return {}

    return _parse_requirement(list(docstring_lines))