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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 create_request(version, method, url, headers):
 """Create a HTTP request header."""

    # According to my measurements using b''.join is faster that constructing a
    # bytearray.
    message = []
    message.append('{} {} HTTP/{}\r\n'.format(method, url, version))
    for name, value in headers:
        message.append(name)
        message.append(': ')
        message.append(value)
        message.append('\r\n')
    message.append('\r\n')
    return s2b(''.join(message))