Update requirements.txt

requirements.txt

@@ -10,6 +10,10 @@ greenlet==0.4.10 ; python_version < '3.7'
 greenlet==0.4.15 ; python_version >= '3.7'
 Jinja2==2.10.1
 libsass==0.17.0
+lxml==3.7.1 ; sys_platform != 'win32' and python_version < '3.7'
+lxml==4.3.2 ; sys_platform != 'win32' and python_version == '3.7'
+lxml==4.6.5 ; sys_platform != 'win32' and python_version > '3.7'  # min version = 4.5.0 (Focal - with security backports)
+lxml ; sys_platform == 'win32'
 Mako==1.0.7
 MarkupSafe==1.1.0
 mock==2.0.0
@@ -20,6 +24,8 @@ Pillow==5.4.1 ; python_version < '3.7' or sys_platform != 'win32'
 Pillow==6.1.0 ; sys_platform == 'win32' and python_version >= '3.7'
 polib==1.1.0
 psutil==5.6.6
+psycopg2==2.7.7; sys_platform != 'win32' and python_version < '3.8'
+psycopg2==2.8.5; sys_platform == 'win32' or python_version >= '3.8'
 pydot==1.4.1
 python-ldap==3.1.0; sys_platform != 'win32'
 pyparsing==2.2.0