Update conda_build.py for opencv dependency(#25654)

paddle/scripts/conda_build.py

@@ -51,6 +51,7 @@ requirements:
     - astor
     - gast>=0.3.3
     - matplotlib
+    - opencv>=3.4.2
 """
 
         self.requirement_run_windows = r"""
@@ -70,7 +71,7 @@ requirements:
     - gast>=0.3.3
     - py-cpuinfo==5.0.0
 """
-        self.test = """
+        self.test = r"""
 test:
   import:
     paddle
@@ -219,9 +220,16 @@ package:
     - matplotlib"""
     if not (cuda_str == None):
         meta_str = meta_str + cuda_str
-    meta_str = meta_str + var.test + var.about
+    
     blt_str = var.blt_const + blt_var
+    if (python_str == var.python27):
+        blt_str = blt_str + """
+    pip install C:\package\opencv_python-4.2.0.32-cp27-cp27m-win_amd64.whl"""
+    else:
+        meta_str = meta_str + """
+    - opencv>=3.4.2"""
     
+    meta_str = meta_str + var.test + var.about
     meta_filename = "meta.yaml"
     build_filename = "bld.bat"
     with open(meta_filename, 'w') as f: