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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 get_proxies():
 """Get available proxies to use with requests library."""

    proxies = getproxies()
    filtered_proxies = {}
    for key, value in proxies.items():
        if key.startswith('http://'):
            if not value.startswith('http://'):
                filtered_proxies[key] = 'http://{0}'.format(value)
            else:
                filtered_proxies[key] = value
    return filtered_proxies