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ua->get( $url )
$ua->get( $url , $field_name => $value, ... )
This method will dispatch a GET request on the given $url. Further arguments can be given to initialize the headers of the request. These are given as separate name/value pairs. The return value is a response object. See HTTP::Response for a description of the interface it provides.

Fields names that start with ":" are special. These will not initialize headers of the request but will determine how the response content is treated. The following special field names are recognized:

:content_file => $filename
:content_cb => \&callback
:read_size_hint => $bytes