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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_cart(base_url, env, cart_name):
 """ returns a dict object representing a cart stored in pulp base_url: a str for the base_url (eg: http://sweet.pulp.repo/pulp/api/) env: a str with the the name of the environement (eg: prod) cart_name: a str with the name of the cart to get """

    base_url = base_url.replace('/pulp/api/', '/pulp/repos')
    url = '%s/%s/carts/%s.json' % (base_url, env, cart_name)

    rsock = urllib2.urlopen(url)
    data = rsock.read()
    rsock.close()

    return load_json_str(data)