def __init__(self, sam_template, managed_policy_loader):
self.sam_template = sam_template<EOL>self.managed_policy_loader = managed_policy_loader<EOL>self.sam_parser = parser.Parser()<EOL>
Construct a SamTemplateValidator

Design Details:

managed_policy_loader is injected into the `__init__` to allow future expansion
and overriding capabilities. A typically pattern is to pass the name of the class into
the `__init__` as keyword args. As long as the class 'conforms' to the same 'interface'.
This allows the class to be changed by the client and allowing customization of the class being
initialized. Something I had in mind would be allowing a template to be run and checked
'offline' (not needing aws creds). To make this an easier transition in the future, we ingest
the ManagedPolicyLoader class.

Parameters
----------
sam_template dict
    Dictionary representing a SAM Template
managed_policy_loader ManagedPolicyLoader
    Sam ManagedPolicyLoader