diff --git a/.idea/workspace.xml b/.idea/workspace.xml
index 4a4a418..a691495 100644
--- a/.idea/workspace.xml
+++ b/.idea/workspace.xml
@@ -2,7 +2,7 @@
 <project version="4">
   <component name="ChangeListManager">
     <list default="true" id="aa6c2199-1a12-49e5-87b6-7ea25345c196" name="Default" comment="">
-      <change type="NEW" beforePath="" afterPath="$PROJECT_DIR$/.idea/vcs.xml" />
+      <change type="MOVED" beforePath="$PROJECT_DIR$/read_a2.py" afterPath="$PROJECT_DIR$/aria2_to_magnet.py" />
       <change type="MODIFICATION" beforePath="$PROJECT_DIR$/.idea/workspace.xml" afterPath="$PROJECT_DIR$/.idea/workspace.xml" />
       <change type="MODIFICATION" beforePath="$PROJECT_DIR$/README.md" afterPath="$PROJECT_DIR$/README.md" />
     </list>
@@ -14,16 +14,16 @@
     <option name="LAST_RESOLUTION" value="IGNORE" />
   </component>
   <component name="CoverageDataManager">
-    <SUITE FILE_PATH="coverage/read_aria2c$read_a2.coverage" NAME="read_a2 Coverage Results" MODIFIED="1511083737189" SOURCE_PROVIDER="com.intellij.coverage.DefaultCoverageFileProvider" RUNNER="coverage.py" COVERAGE_BY_TEST_ENABLED="true" COVERAGE_TRACING_ENABLED="false" WORKING_DIRECTORY="$PROJECT_DIR$" />
+    <SUITE FILE_PATH="coverage/read_aria2c$read_a2.coverage" NAME="read_a2 Coverage Results" MODIFIED="1511092968045" SOURCE_PROVIDER="com.intellij.coverage.DefaultCoverageFileProvider" RUNNER="coverage.py" COVERAGE_BY_TEST_ENABLED="true" COVERAGE_TRACING_ENABLED="false" WORKING_DIRECTORY="$PROJECT_DIR$" />
   </component>
   <component name="ExecutionTargetManager" SELECTED_TARGET="default_target" />
   <component name="FileEditorManager">
     <leaf SIDE_TABS_SIZE_LIMIT_KEY="450">
-      <file leaf-file-name="read_a2.py" pinned="false" current-in-tab="false">
-        <entry file="file://$PROJECT_DIR$/read_a2.py">
+      <file leaf-file-name="aria2_to_magnet.py" pinned="false" current-in-tab="false">
+        <entry file="file://$PROJECT_DIR$/aria2_to_magnet.py">
           <provider selected="true" editor-type-id="text-editor">
-            <state relative-caret-position="-1620">
-              <caret line="3" column="0" lean-forward="true" selection-start-line="3" selection-start-column="0" selection-end-line="32" selection-end-column="66" />
+            <state relative-caret-position="432">
+              <caret line="57" column="0" lean-forward="false" selection-start-line="57" selection-start-column="0" selection-end-line="57" selection-end-column="0" />
               <folding>
                 <element signature="e#0#13#0" expanded="true" />
               </folding>
@@ -34,8 +34,8 @@
       <file leaf-file-name="README.md" pinned="false" current-in-tab="true">
         <entry file="file://$PROJECT_DIR$/README.md">
           <provider selected="true" editor-type-id="text-editor">
-            <state relative-caret-position="540">
-              <caret line="15" column="27" lean-forward="true" selection-start-line="15" selection-start-column="27" selection-end-line="15" selection-end-column="27" />
+            <state relative-caret-position="440">
+              <caret line="56" column="3" lean-forward="false" selection-start-line="56" selection-start-column="3" selection-end-line="56" selection-end-column="3" />
               <folding />
             </state>
           </provider>
@@ -44,7 +44,7 @@
       <file leaf-file-name="__builtin__.py" pinned="false" current-in-tab="false">
         <entry file="file://$USER_HOME$/.PyCharm2017.1/system/python_stubs/-762174762/__builtin__.py">
           <provider selected="true" editor-type-id="text-editor">
-            <state relative-caret-position="-153">
+            <state relative-caret-position="15156">
               <caret line="421" column="4" lean-forward="false" selection-start-line="421" selection-start-column="4" selection-end-line="421" selection-end-column="4" />
               <folding />
             </state>
@@ -126,8 +126,8 @@
       <foldersAlwaysOnTop value="true" />
     </navigator>
     <panes>
-      <pane id="Scope" />
       <pane id="Scratches" />
+      <pane id="Scope" />
       <pane id="ProjectPane">
         <subPane>
           <PATH>
@@ -179,8 +179,8 @@
       <option name="ADD_SOURCE_ROOTS" value="true" />
       <module name="read-aria2c" />
       <EXTENSION ID="PythonCoverageRunConfigurationExtension" enabled="false" sample_coverage="true" runner="coverage.py" />
-      <option name="SCRIPT_NAME" value="$PROJECT_DIR$/read_a2.py" />
-      <option name="PARAMETERS" value="" />
+      <option name="SCRIPT_NAME" value="C:\Users\hzx\PycharmProjects\read-aria2c\aria2_to_magnet.py" />
+      <option name="PARAMETERS" value="-f dahufa.aria2" />
       <option name="SHOW_COMMAND_LINE" value="false" />
       <option name="EMULATE_TERMINAL" value="false" />
       <method />
@@ -359,16 +359,15 @@
     <frame x="-8" y="-8" width="1936" height="1056" extended-state="6" />
     <editor active="true" />
     <layout>
+      <window_info id="Project" active="false" anchor="left" auto_hide="false" internal_type="DOCKED" type="DOCKED" visible="true" show_stripe_button="true" weight="0.1880388" sideWeight="0.5" order="0" side_tool="false" content_ui="combo" />
       <window_info id="TODO" active="false" anchor="bottom" auto_hide="false" internal_type="DOCKED" type="DOCKED" visible="false" show_stripe_button="true" weight="0.33" sideWeight="0.5" order="6" side_tool="false" content_ui="tabs" />
       <window_info id="Event Log" active="false" anchor="bottom" auto_hide="false" internal_type="DOCKED" type="DOCKED" visible="false" show_stripe_button="true" weight="0.33" sideWeight="0.5" order="7" side_tool="true" content_ui="tabs" />
+      <window_info id="Database" active="false" anchor="right" auto_hide="false" internal_type="DOCKED" type="DOCKED" visible="false" show_stripe_button="true" weight="0.33" sideWeight="0.5" order="3" side_tool="false" content_ui="tabs" />
       <window_info id="Version Control" active="false" anchor="bottom" auto_hide="false" internal_type="DOCKED" type="DOCKED" visible="false" show_stripe_button="true" weight="0.33" sideWeight="0.5" order="7" side_tool="false" content_ui="tabs" />
       <window_info id="Python Console" active="false" anchor="bottom" auto_hide="false" internal_type="DOCKED" type="DOCKED" visible="false" show_stripe_button="true" weight="0.33" sideWeight="0.5" order="7" side_tool="false" content_ui="tabs" />
       <window_info id="Run" active="false" anchor="bottom" auto_hide="false" internal_type="DOCKED" type="DOCKED" visible="true" show_stripe_button="true" weight="0.33028573" sideWeight="0.5" order="2" side_tool="false" content_ui="tabs" />
-      <window_info id="Terminal" active="false" anchor="bottom" auto_hide="false" internal_type="DOCKED" type="DOCKED" visible="false" show_stripe_button="true" weight="0.33" sideWeight="0.5" order="7" side_tool="false" content_ui="tabs" />
-      <window_info id="Project" active="false" anchor="left" auto_hide="false" internal_type="DOCKED" type="DOCKED" visible="true" show_stripe_button="true" weight="0.18534483" sideWeight="0.5" order="0" side_tool="false" content_ui="combo" />
-      <window_info id="Database" active="false" anchor="right" auto_hide="false" internal_type="DOCKED" type="DOCKED" visible="false" show_stripe_button="true" weight="0.33" sideWeight="0.5" order="3" side_tool="false" content_ui="tabs" />
-      <window_info id="Find" active="false" anchor="bottom" auto_hide="false" internal_type="DOCKED" type="DOCKED" visible="false" show_stripe_button="true" weight="0.3295325" sideWeight="0.5" order="1" side_tool="false" content_ui="tabs" />
       <window_info id="Structure" active="false" anchor="left" auto_hide="false" internal_type="DOCKED" type="DOCKED" visible="false" show_stripe_button="true" weight="0.25" sideWeight="0.5" order="1" side_tool="false" content_ui="tabs" />
+      <window_info id="Terminal" active="false" anchor="bottom" auto_hide="false" internal_type="DOCKED" type="DOCKED" visible="false" show_stripe_button="true" weight="0.33" sideWeight="0.5" order="7" side_tool="false" content_ui="tabs" />
       <window_info id="Favorites" active="false" anchor="left" auto_hide="false" internal_type="DOCKED" type="DOCKED" visible="false" show_stripe_button="true" weight="0.33" sideWeight="0.5" order="2" side_tool="true" content_ui="tabs" />
       <window_info id="Debug" active="false" anchor="bottom" auto_hide="false" internal_type="DOCKED" type="DOCKED" visible="false" show_stripe_button="true" weight="0.5781072" sideWeight="0.5" order="3" side_tool="false" content_ui="tabs" />
       <window_info id="Data View" active="false" anchor="right" auto_hide="false" internal_type="DOCKED" type="DOCKED" visible="false" show_stripe_button="true" weight="0.33" sideWeight="0.5" order="3" side_tool="false" content_ui="tabs" />
@@ -377,6 +376,7 @@
       <window_info id="Commander" active="false" anchor="right" auto_hide="false" internal_type="DOCKED" type="DOCKED" visible="false" show_stripe_button="true" weight="0.4" sideWeight="0.5" order="0" side_tool="false" content_ui="tabs" />
       <window_info id="Inspection" active="false" anchor="bottom" auto_hide="false" internal_type="DOCKED" type="DOCKED" visible="false" show_stripe_button="true" weight="0.4" sideWeight="0.5" order="5" side_tool="false" content_ui="tabs" />
       <window_info id="Hierarchy" active="false" anchor="right" auto_hide="false" internal_type="DOCKED" type="DOCKED" visible="false" show_stripe_button="true" weight="0.25" sideWeight="0.5" order="2" side_tool="false" content_ui="combo" />
+      <window_info id="Find" active="false" anchor="bottom" auto_hide="false" internal_type="DOCKED" type="DOCKED" visible="false" show_stripe_button="true" weight="0.3295325" sideWeight="0.5" order="1" side_tool="false" content_ui="tabs" />
       <window_info id="Ant Build" active="false" anchor="right" auto_hide="false" internal_type="DOCKED" type="DOCKED" visible="false" show_stripe_button="true" weight="0.25" sideWeight="0.5" order="1" side_tool="false" content_ui="tabs" />
     </layout>
   </component>
@@ -393,7 +393,49 @@
     <watches-manager />
   </component>
   <component name="editorHistoryManager">
-    <entry file="file://$PROJECT_DIR$/read_a2.py">
+    <entry file="file://$PROJECT_DIR$/aria2_to_magnet.py">
+      <provider selected="true" editor-type-id="text-editor">
+        <state relative-caret-position="72">
+          <caret line="3" column="0" lean-forward="false" selection-start-line="3" selection-start-column="0" selection-end-line="32" selection-end-column="66" />
+          <folding>
+            <element signature="e#0#13#0" expanded="true" />
+          </folding>
+        </state>
+      </provider>
+    </entry>
+    <entry file="file://$USER_HOME$/.PyCharm2017.1/system/python_stubs/-762174762/__builtin__.py">
+      <provider selected="true" editor-type-id="text-editor">
+        <state relative-caret-position="15156">
+          <caret line="421" column="4" lean-forward="false" selection-start-line="421" selection-start-column="4" selection-end-line="421" selection-end-column="4" />
+          <folding />
+        </state>
+      </provider>
+    </entry>
+    <entry file="file://$USER_HOME$/.PyCharm2017.1/system/python_stubs/-762174762/_struct.py">
+      <provider selected="true" editor-type-id="text-editor">
+        <state relative-caret-position="2232">
+          <caret line="62" column="13" lean-forward="false" selection-start-line="62" selection-start-column="12" selection-end-line="62" selection-end-column="13" />
+          <folding />
+        </state>
+      </provider>
+    </entry>
+    <entry file="file://$USER_HOME$/.PyCharm2017.1/system/python_stubs/-762174762/binascii.py">
+      <provider selected="true" editor-type-id="text-editor">
+        <state relative-caret-position="468">
+          <caret line="13" column="11" lean-forward="false" selection-start-line="13" selection-start-column="4" selection-end-line="13" selection-end-column="11" />
+          <folding />
+        </state>
+      </provider>
+    </entry>
+    <entry file="file://$PROJECT_DIR$/README.md">
+      <provider selected="true" editor-type-id="text-editor">
+        <state relative-caret-position="540">
+          <caret line="15" column="27" lean-forward="true" selection-start-line="15" selection-start-column="27" selection-end-line="15" selection-end-column="27" />
+          <folding />
+        </state>
+      </provider>
+    </entry>
+    <entry file="file://$PROJECT_DIR$/aria2_to_magnet.py">
       <provider selected="true" editor-type-id="text-editor">
         <state relative-caret-position="0">
           <caret line="0" column="0" lean-forward="false" selection-start-line="0" selection-start-column="0" selection-end-line="0" selection-end-column="0" />
@@ -437,16 +479,16 @@
     </entry>
     <entry file="file://$USER_HOME$/.PyCharm2017.1/system/python_stubs/-762174762/__builtin__.py">
       <provider selected="true" editor-type-id="text-editor">
-        <state relative-caret-position="-153">
+        <state relative-caret-position="15156">
           <caret line="421" column="4" lean-forward="false" selection-start-line="421" selection-start-column="4" selection-end-line="421" selection-end-column="4" />
           <folding />
         </state>
       </provider>
     </entry>
-    <entry file="file://$PROJECT_DIR$/read_a2.py">
+    <entry file="file://$PROJECT_DIR$/aria2_to_magnet.py">
       <provider selected="true" editor-type-id="text-editor">
-        <state relative-caret-position="-1620">
-          <caret line="3" column="0" lean-forward="true" selection-start-line="3" selection-start-column="0" selection-end-line="32" selection-end-column="66" />
+        <state relative-caret-position="432">
+          <caret line="57" column="0" lean-forward="false" selection-start-line="57" selection-start-column="0" selection-end-line="57" selection-end-column="0" />
           <folding>
             <element signature="e#0#13#0" expanded="true" />
           </folding>
@@ -455,8 +497,8 @@
     </entry>
     <entry file="file://$PROJECT_DIR$/README.md">
       <provider selected="true" editor-type-id="text-editor">
-        <state relative-caret-position="540">
-          <caret line="15" column="27" lean-forward="true" selection-start-line="15" selection-start-column="27" selection-end-line="15" selection-end-column="27" />
+        <state relative-caret-position="440">
+          <caret line="56" column="3" lean-forward="false" selection-start-line="56" selection-start-column="3" selection-end-line="56" selection-end-column="3" />
           <folding />
         </state>
       </provider>
diff --git a/README.md b/README.md
index 4578ee7..bb8b45f 100644
--- a/README.md
+++ b/README.md
@@ -42,4 +42,16 @@ also @alphatr write a tool transform .aria2 file to a magnet link use javascript
 # more detail
 # https://aria2.github.io/manual/en/html/technical-notes.html
 # ================================================================
+```
+
+# how to run
+
+```
+python.exe aria2_to_magnet.py -f dahufa.aria2
+
+```
+
+output
+```
+magnet:?xt=urn:btih:959E2ECEB954313D3869EFF7924CA7CD8DE739
 ```
\ No newline at end of file
diff --git a/read_a2.py b/aria2_to_magnet.py
similarity index 88%
rename from read_a2.py
rename to aria2_to_magnet.py
index 5ce67bc..363dd4b 100644
--- a/read_a2.py
+++ b/aria2_to_magnet.py
@@ -1,5 +1,12 @@
 import struct
 import binascii
+import argparse
+
+parser = argparse.ArgumentParser()
+parser.add_argument("-f", "--file", required=True,
+                    help="input file XXX.aria2")
+
+args = parser.parse_args()
 
 
 # ================================================================
@@ -40,14 +47,14 @@ def parse_aria_control_file(file_name):
             version = f.read(2)
 
             i = int(version.encode('hex'), 16)
-            print "version is " + str(i)
+            # print "version is " + str(i)
 
             # skip  EXT, find info  hash_binary length
             f.seek(6)
 
             length = f.read(4)
             hash_length = int(length.encode('hex'), 16)
-            print "hash length is " + str(hash_length)
+            # print "hash length is " + str(hash_length)
 
             # read next hash_length
             f.seek(10)  # Go to info hash
@@ -67,7 +74,8 @@ def parse_aria_control_file(file_name):
 
 
 if __name__ == '__main__':
-    parse_aria_control_file("dahufa.aria2")
+    file_name = args.file
+    parse_aria_control_file(file_name)
     # version is 1
     # hash length is 20
     # magnet:?xt=urn:btih:959E2ECEB954313D3869EFF7924CA7CD8DE739